It might be that I don't take the work as seriously as them... I am a part-timer with plans for grad school, whereas many of my co-workers and obviously my bosses are in it for the long term, trying to get promoted etc. Although, even when I have a lot on my plate I still do make a bit of an effort to connect... but, that could be where the instinctual difference comes into play.
With my SP-first friends, it definitely is quite different. There is an effort to connect, albeit often in a more sober style than with my other friends. There seems to be a much greater drive to discuss important topics such as career aspirations in a serious capacity, and to connect over them.
I was actually with two friends last night who are likely both SP-firsts. These two in particular seem much more inclined to 'talk shop' than to just relax and joke around. This is in sharp contrast with my close Sx-first ENTP friend. With him it is pretty rare that the conversation gets super serious... the closest thing would be us having pretentious conversations about our passions, etc. Lol.
One of the other people I mentioned is an ISTP 9w8 sp/sx most likely. With him I am starting to get the feeling that he simply doesn't care enough to want to build many relationships in general. :P