>>4533756A tomboy is in general a girl who partakes in masculine hobbies and values and doesn't put much value into definitely-feminine things. While being high-energy is a part of that nobody who has deep rooted confidence issues related to her feminine appeal, goes to a beauty salon and takes a bath three times a day can be called one. You are mistaking the reason why those traits appeared in her character in the first place and just how different she is from other holos in terms of her upbringing. Being easily flustered by compliments is most definitely a feminine trait, as is bursting into tears on a spot because of sentimental reminders of the past, as is worrying about making a slightest mistake before an audience, as is being frustrated because someone doesn't give you enough attention, as is being picky about food, as are countless other things Subaru exhibits on a regular basis. Sure, some tomboy traits are definitely there, like for example preferring comfortable "boyish" clothes over inconvenient feminine fashion, but to focus on just that and say it defines her is cherrypicking.
You focus on her 3D performances but that's not her normal streams, in fact it's farthest from an honest unscripted show of character. Subaru like a lot of other holos (see Kanata's 3D debut, a shut-in working herself to near death by moving so much) doesn't stop moving because it's good showmanship. Same reason she doesn't allow herself to fall silent for extended periods of time during streams and especially during collabs. For some holos it's acceptable because they don't put that much attention into their performance. It is just one outlet to her expression, one that is on a strict schedule and has to be high-energy to not be boring. A lot of holos are also high-energy on stage, a lot of them don't shut up either, easiest example that fits all four of your parameters is Fubuki. If we take out "easily flustered" a LOT more holos fit into this, even Korone. Korone fits this even more because of how rough, assertive and outwardly confident she presents herself, which is completely opposite of Subaru.
