Yes, I have seen a lot of cis-women act like Gigi Gorgeous does. The thing is, they were mostly teenagers, and mostly in that phase of needing to assert their newfound femininity to the world. Yes, there are women who behave like this as adults too, (and I mostly find them obnoxious,) but it does become increasingly uncommon as distance from puberty progresses. I had a lot of female friends who were girls with a capital G around age 12-13, speaking like valley girls and going completely over-the-top with cutesy behavior, but then by the time they graduated college they abruptly mellowed out and got much more down-to-earth.
It can be tough for trans women. I often feel like I'm in a state of perpetual puberty, where I'm always lacking confidence in my femininity and thus need to prove it somehow by being more feminine. And I feel like that's basically what people who act like this are doing, trans or cis, regardless of age. They're trying to assert their femaleness to the world.
My roommate is also very over-the-top in terms of flaunting her femininity. She wears skirts everywhere (and criticizes me for wearing jeans too much,) is constantly talking to other people about how she's a girl, every single conversation I have with her eventually ends in some story about how "they just see another woman," she whines about having to wear a unisex uniform to work, is constantly going on about makeup, constantly walking around the house in nothing but a bra and panties (and I can tell she's doing it to say "look! I have boobs! I'm a woman!",) using way too many kissy noises and cutesy emoticons whenever she's chatting with her internet boyfriend, and frankly she does really annoy me with this. I personally feel like she's really overdoing it, and overcompensating, and it's like being in high school all over again where the girls would constantly make me roll my eyes because all they ever talked about was boys, makeup, and fashion, and I felt like the fun kids I was friends with weren't even in there anymore.
But at the same time, who am I to judge? My roommate is happy. She's constantly smiling, constantly having fun, and I can tell that every single time she gets to act feminine and be accepted as a woman she just smiles so brightly inside. Gigi is that way too. She's always happy in her videos, and always upbeat and bubbly. Where I know I come across as VERY reserved and calm and logical in my videos. And yet I'm always "meh" mood-wise, and always doubting myself, and always going into dysphoric freakouts because I'm worried that I'm somehow not "female enough." So as much as I hate the super-feminine expressions and feel like they're just an overcompensating act, who am I to judge? Who am I to tell someone else how to be happy, when they're already happy, while I'm often not? Just because my own personal values and what I view as "genuine femininity" differs from theirs, clearly it works for them, so I don't really feel like I have a right to say anything.
Yes, I do MUCH prefer the calm passive expression style. To me, it feels more honest and more real. That to me says "authentic femininity," someone who is comfortable in their femaleness and doesn't need to put on an act to prove it to other people. (The same way that I feel about men who are calm, and don't feel the need to constantly talk about sex and booze and fast cars and drunken escapades in Las Vegas to prove their masculinity.) But again, I feel wrong judging people who are happy with themselves.