I noticed increased frequency of posts in places like r/rpghorrorstories, that describe a situation where the player brings a tiny veiled or just a shameless copy of a popular fictional character - Sokka, Scanlan, John Snow, Walter White - except "more based" or "less of a cuck". What follows is a story of the player doing some horrible manosphere shit.
I know that a lot of posts on places like these are fake, but in this case I kinda hope they are. Or that it's all the same guys at different tables. Either is more comforting that an idea of an army of incels trying to rp their extremely toxic fanfiction on the table.
I haven't encountered this. But if anyone said "based" or "cuck" at me, I would have serious questions about if they're a good fit for my group.
Based is one that, as another user said, could go either way. Its original use is very alt-right, but today I personally probably see it used more in support of leftist ideals.
Cuck certainly is much more of a red flag. I have seen it used ironically by people whom I have reason to respect, but it's far more likely to be the source of some serious questions.
A group of friends uses "based and budfilled" mostly sarcastically.