Evil?Yes but actually no

If they ask you for spoilers, they deserve it.

This is actually what I do, I tend to "let slip" fake spoilers so people will be more shocked and surprised by events in the film

I've watched it.
Its a rollercoaster of emotions.
All the actors carried it.
Also very very different from Infinity War.
I think it deserves an Oscar for Best picture.

Or even better: say something that was in the movie that's so small and inconsequential that no one believes you, and when it happens they say "fuck he was right"
Like this: the after credits scene of captain marvel is a cat throwing up