So wait, are you just talking about having one-on-one convos about The Age of Innocence (or whatever) and having the person you're talking to be the one to go, "Boy wait until you get to the part where..."?

Because if so then yeah, that's a pretty shitty move. I thought you were just broadly complaining about the general statute of limitations for spoiling classic literature.

I mean, are you complaining about spoilers in 100+ year old novels like Jane Eyre or some shit? I get that having an unspoiled story is nice but if that's the case then you really cannot expect all of society to just stop discussing pretty widely disseminated stories just because you haven't gotten there yet.

(Obvi does not apply to spoiling recent works.)

And that's admirable! But I feel like either you've got to come up with incredibly arbitrary terms to use which just feel made up and hard to understand the connotations of ("Yuck, that dude is such a gooseberry!"), or you pick another term which already has sort of negative vibes ("I thought that book was really sludgy"), but you have to work to wrap the word around a meaning it doesn't have. And either way, it feels inevitable that if either of them caught on, they would be applied to ostracized groups in a way that would bring us right back to where we started ("I hate that dude, he's such a gooseberry" -> "You shouldn't call people gooseberries, it's got an ableist history".)

What more creative insults did you come up with, out of curiosity?

Every negative term has been wielded against ostracized groups. At some point you have to stop blacklisting words for that reason, or you're going to simply run out of negative words to use.