You can't exactly poll for this online because it'll be determined by the kind of place you're asking, like preddit is obviously going to be dominated by soys and 4chan probably RW depending on the board, so I would say it can only be speculated on without the ability to run a formalized study.

So, what does your choice of faction say about you. Idk about the state of SC2 these days but Brood Wars seemed pretty much balanced all three ways so there was no reason to choose based on viability alone.

I think it's a somewhat interesting question because thematically, it's pretty clear that they were going with a heaven/hell/earth aesthetic. Terran being man and originally of Earth, Zerg being only what can be described as demons as though from hell, and Protoss are otherworldly almost angelic aliens with architecture reminiscent of what you might imagine heaven would have. A very cool general aesthetic and theme for a game, but also very simple, and each one is going to attract certain kinds of people differently.

Also I know I said polling one specific place isn't useful for answering the question, but purely out of curiosity: https://strawpoll.com/polls/6QnM7aAWVZe

I choose Terran, myself. I've always like Terran the most even before becoming politically aware but I also see it as the general default RW choice due to their presentation.