I saw a comment by someone on reddit who said they no longer comment on any fanfiction because of the risk of it being AI and ... that just seems like such a cop out to me, not to mention incredibly cruel to authors.
Please please please do not stop commenting on all fics or interacting with authors because you are worried about things being AI. The risk is slim, and the damage you do to authors by doing this is awful.
Writers put so much effort into their fics. For people to openly admit they still read and consume these fics, but choose not to comment on anything because of the possibility of someone using AI for their writing is incredibly selfish. You're punishing authors by doing this. You're not being moral or helpful or crusading for any useful cause - you're just hurting authors.
Ironically, by doing this, you're actually more likely to cause authors to stop writing (silence does this), and people who can't write will fill the gaps left by creating AI writing - so you're making the problem worse, not helping anyone.
If you want to support authors and writers, then SUPPORT them! Reblog work and send authors asks, leave comments and kudos, and above all don't punish people with silence.
It says a lot about the world we live in that AO3 closed guest comments today because of an influx of nasty spam comments accusing people of writing fics using AI.