It's just the US-skew I think, Americans (cold war hangover perhaps?) seem to me to make much more of 'capitalism' as a concept that is common for people to have a binary opinion on; if you've noticed a recent change I'd suggest it's reaction against the current Trump presidency, making perhaps left/Democrat-leaning 'anti-capitalist' views more vocal.

Just how it seems to me from the UK/Europe, obviously capitalist countries and actual socialism certainly a minority stance, but it's just not such a big deal at all. I don't even think they really mean 'capitalist' though, it's more like what would be framed here as 'tax mega corps more' or 'no more non-doms' or calls to block anti-competitive mergers. A debate baselined at the extreme of capitalism perhaps, whether there should be any controls at all, or everything left to the free market.