It seems more energetic because of how she edited it, I think. Usually with introverts, there tends to be a pause between thoughts when speaking... and because she cut out the gaps, you can't really get a full sense of her speech mannerisms.
Apparently i'm 4w3 and I am not really like the OP video. I've even done acting and performing, and I still don't come out at the camera like that (i've made a few videos I've discarded). I would say I can be very silly, playful and i'm usually really easy going. But when I watch over them, they are a little more relaxed and reserved energy wise. My intj sister can be pretty "out there" and crazy, but it's more punctuated and the energy flow is still more contained than an extravert's might be. It's hard to explain, but i'm talking about sensing the energy flow. I notice enfps' tend to jump from idea to idea... I just don't do that. I generally stay on track with what i'm talking about, and then integrate it with other ideas. That jumpiness kind of disconcerts me. I need a bit of time to think and mull over, rather than move quickly through different ideas.
I use hand gestures (around friends) and voice tones (around friends) and I can be quite expressive (depending on the context). I had to learn to get through my reservations though (I used to hate public speaking, but now I'm used to it and I can be quite effective at communicating, when i'm given time to prepare). You see a different side of me when I know you and like you. If you don't know me, i'm not overtly expressive but I can still talk to people. If you know me better, you see the more expressive, passionate (yet still reserved) side of me.
I wouldn't say i'm bubbly at all. I'm more friendly, easy going and warm (more around friends). Sociable? not really. I get on ok with people, sure. But I'm not running around sitting on peoples laps at parties and shaking everyones hands, you know? I can be a good host, introduce people, get things rolling... but I'm not "out there" about it. I hate being the center of attention in a social setting. I'm a self pres/sexual in the enneagram, so I much prefer 1 on 1 interactions with someone I like, than being in a group, which kind of restricts my sociability tendencies. I prefer observing the group and interacting with one or two people in a more intimate setting (I usually approach).
I'm not very open about myself at all. I've only just learned through posting on this forum how to be open about myself.