Depends on how it is shown it could be at least tolerable. Hakai no Miko present the "future events" in pov of future people who hates and fear the protagonist or too distant future the facts got muddled . Their biases give unreliable narrator element to it.
See, in that case, I don't count it as the story telling you the plot points, I count that as 'foreboding' or if it's super unreliable, on the edge of even 'foreshadowing.'
Like those fictions that revolve around knowing a snippet of the future, and not being able to change it, but being able to change the after.
Think Back to the Future With Doc and the bullet-proof vest. Yes, Doc got gunned down still, but afterwards, he was still alive.
Hinting at the future ain't bad, it's when the Omnipresent narrator states/shows it as a fact that I have a problem with it. Like that one 'isekai'd as a fish' manhwau(maybe manga), looked interesting, but I instantly knew the end point, and also lets me know the story is rushing towards that point becuase it's 'where it gets good.'
If they're gonna spoil exactly what happens, at least make it up in the air, like, make it a 'might' instead of a 'will,' or better yet, make it ambiguous or from an unreliable narrator(like you said.)