Quite generally, one could describe the introverted standpoint as one that under all circumstances sets the self and the subjective psychological process above the object and the objective process, or at any rate holds its ground against the object.
When reading Jung, we must distinguish the object of his study from his understanding of the object. The main object being introversion/extraversion. It is absolutely preponderant to understand when finishes the description and starts the analyzis, in order to seize the object as it is and eventually correct prior conclusions. Jung's understanding of the phenomenon was that of a man of his time, influenced by the thoughts of Goethe among others, scientific trends, how society worked, how people reacted to it and of course, his personal flaws and delusions.
What Jung merely observed is a well studied mechanism. The human mind doesn't have any natural intuition of what is reality, what is fantasy, hence any natural drive to subordinate its prognoses to reality.
The essential aspect of reality is its consistency, and yet, we don't have for function to be consistent ourselves. That's why we don't last long and all sort of intellectual disorders creep in. However, we have one that comes close and can eventually be tuned to gain in consistency : the need to avoid cognitive dissonance, either through modifications of the prognosis, or the situation.
The former is extraversion and the latter, introversion. The former strategy is to withdraw our prognoses, the way we habitually react to perceived events, and the latter is to protect those habits until eventually the situation rules in their favour again.
Those two ways of solving cognitive dissonance, although antagonistic, are necessary in order to adapt our thoughts to reality all while protecting them from disinformation. However, an improper calibration of this trust/defiance system will allow disinformation to corrupt one's thoughts, from the outside if overly extraverted, or the inside, if overly introverted.
This echoes the matter of distinguishing the reality of this intro/extraversion mechanism from any misinformation that could come from Jung or any of his self-proclaimed scholars, or even me, when our own attitude can distort the fine line, or epistemological function, between the perception of its characteristics from the perception of what one thinks it is, because introversion makes us vulnerable to our own confirmation bias, whereas extraversion makes us vulnerable to that of others.
I will give you my .02€ about that fine line at the end.
So to summarize, an attitude is a whole perception/judgment process, as it is all about protecting or adapting one's habits of reacting to certain informations. In the case of introversion, the individual will reinforce a decision by cherry picking the informations that confirm it. What this implies is that when introversion dominates, to keep with this example, the whole perception/judging process is introverted. The individual seeks knowledge and patterns that confirm its thoughts and favor them in its judgments.
The dominant attitude of consciousness, so as Jung named it, is not reversed from perception to judgment. What has been reversed, however, is the definition of what introverted and extraverted judgements are. An introvert is an introvert. To be more specific, an introverted perceiver is an introverted judger.
There has been quite a lot of cherry picking going in order to protect a certain fallacy of Jung regarding introversion and extraversion. So let's talk about what it is and why it doesn't work.
Jung viewed this E/I attitude as a mere extension of a more universal phenomenon, and he was right, it is just the way things evolve in this universe, trends either change or reinforce themselves. If you think about it, life is fundamentally introverted. At the origin, it's a mechanism that turns its environment into itself and that's why it is so effective, unless, unless... it ends up being its own hostile environment. I'm almost disgressing... but the point is, introversion is by nature invasive, even though the invasive mind might sometimes appear to be on the defensive, never leaving one's territory, to the point of paranoia, that's only up to how much of one's environment the introvert needs to control in order confirm one's prognoses.
But for Jung, the introvert couldn't be invasive, outgoing, because he was under the influence of the belief that outgoingness is being open to change, and so was sexuality. In a certain sense, sexual reproduction is a form of perpetuation (of habits) that changes the genetic content of the individual hence the habits. But that's only up to how one is driven to breed with genetically different mates. And we know that it isn't exactly the trend there, rather, a fortuitous outcome resulting from the inconsistency of one's drives. This sexual drive, the "libido", that drives people to connect and socialize, is not an act of extraversion.
But don't forget, Jung was a man of his time, he couldn't interact with as many people as we do now. He was dealing with more deceiving patterns that were more likely to lead him to assume a one sided cause-effect relation between gregariousness, outgoingness, sexuality and extraversion.
This fallacy has been the socle on which Jung scholars built systems that reverse the definition of extraverted and introverted judgments, as well as extraversion and introversion per se, reducing it to a vague libidinous sense of social ease and conformism. Of course if could almost make sense : if perception is introverted, then judgements adapt to it. PI=JE. However, how to explain under this assumption that a dominantly extraverted judger would be dominated by one's introverted drive to cherry pick at the perceiving stage? From this assumption, extraversion would always be dominated by introversion. That's the limit of how such inconsistency can pantomime reality.
Now back to this fine line. Protecting oneself is not ultimately wrong, however it does depend on what we are. It only makes sense to protect our ability to gain in consistency for example, as only said ability can understand and solve existential problems. Yet for this to happen, everything else must comply and adapt to the reinforcement of this outcome. And since we aren't born consistent, but inconsistent and misinformed by default, letting introversion dominate over extraversion by default will lead anybody to distort the fine line and build irrealistic systems of thoughts, or if you mean, reactions to one's own issues. However we aren't the only ones to be inconsistent and we'll have to deal with a lot of misinformation so extraversion cannot be allowed either to dominate our creativity by default. Otherwise, the need for knowleldge will creep in and some overlearning will parasite one's ability to redefine one's problems beyond others' abilities. When extraversion dominates the need to understand, one cannot protect oneself from the misunderstanding of another. So the fine line is not a fallacy of the middle ground. Specializing oneself in sapience is an evolutive bottleneck of human personalities.
That's all I had to say. Before you feel like extending this thread, make sure to understand that I won't reply to answers that do not pinpoint inconsistencies in my arguments. This topic is mainly dedicated to all the people who made me repeat the same thing over and over and over for years.