I assumed “thought about being a different gender” in this context meant “actively desiring it irrespective of negative impacts of sexism and gender roles.” Such that, even if one could magically take away those negative impacts, the desire would remain.

For what it’s worth I (cis, a man) have felt less than a man on occasion and have always been more of the quiet, sensitive, bookish type. Sure, I have pondered being another gender briefly here or there – as a thought experiment or trying to empathize, perhaps – but I have never seriously wanted to trade being a man for any reason. I want to stay how I am, actually.

Hopefully this is helpful to some.

There are quite a few mainstream series and movies that touched upon the subject (albeit mostly poorly). So in that regard most people will have at least thought about it once. Probably not for long though.