This topic again?
"Simps" are weak men who allow themselves to be wrapped around a girl's finger with zero reciprocation from the girl herself, and is usually clueless over his own status in her life.
The term is used ironically, to throw shade at
gentlemen following the rules of courtship and getting teased for it; which then the term loses all meaning..... But generally, it is about someone who is willingly placing himself in the "friendzone" despite all he'll do for her.
It's a common phrase used in Twitch, Chaturbate, and across social media, where men will donate money to garner her attention during her streams, long enough to believe she is into him, and in his mind he's her e-girlfriend....when in truth she doesn't care, she has 50,000 followers and makes a 1 million dollars a year.
And since it's mentioned, Incels ( involuntary celibate ) are maladjusted "losers" of the genetic lottery that can't garner the attention of girl through any traditional means at all; but at the same time, believe themselves "worthy" because they still play by those traditional rules. However, they are jaded when they constantly lie to themselves and/or have society itself lie to them. Often mixing nihilistic philosophies with MRAs/MGTOW memes or full-on misogynic rants. Often leading to anti-social behaviour towards events you read about in the news.
Like using the word "simp", it's often used to label anyone facing the direction of such anti-societal philosophies, which again loses all true meaning.