Ok, here are some examples of people treating AO3 like social media or like it has an algorithm (violating the TOS in some cases, just being deeply annoying in others).
Continually updating the date on their work so it gets pushed to the top of the tag, without actually making updates. Not against the TOS, just HORRIBLE behaviour, absolutely rude as fuck, I will mute people who do this with zero hesitation. Everyone gets their turn at the top of the page, you aren't special. (Caveat: people whose work was in an unrevealed/anon collection, like for an exchange or event, get one free redate in my opinion, once their name is attached or the work is revealed. Otherwise stop redating your work to try and get more people to see it.)
Tagging "for reach" rather than based on the content of the work. Stop grabbing every single fandom that might be vaguely related (e.g. if you're writing Dracula fic, don't tag every single fandom with vampires in it). Don't tag your RPF as the FPF fandom too, "so more people will see it." (We will see it, and we'll mute you.) Stop tagging in the main character/relationship fields for characters who appear in one paragraph and never speak, or for relationships that are just implied in the background (use the Additional tags field for those if you want.) Tagging actively wrong fandoms is against the TOS and reportable, tagging inaccurate rels, characters, or additional tags is not against the TOS but just asshole behaviour.
Creating placeholder posts. "Story coming soon!" - go away, I'm muting you, I will never see your story. Against the TOS, reportable.
Treating the Archive like a personal journal, making updates just to complain about how mean people are being to you, or how you can't update this week because you're sick, or just repeating your fave ship name 1000 times or whatever. Put it on tiktok , tumblr, bluesky, whatever. Put a link to your social media in your profile or author's note. Non-fanworks are against the TOS.
Acting like it's weird to comment on older works. It's an archive. It's there to preserve fanworks for as long as possible. Those works are there for you to read. You can comment on them even if they're 10, 15, 50 years old. It's fine. If the author didn't want comments, they can disable comments. If they have comments turned on, assume they want you to comment.
Complaining that they want AO3 to recommend similar works to them based on their reading habits/preferences. No, you don't want this. You do not want AO3 to track your reading and push works it thinks might be similar to you, not least because good lord what a terrible idea. AO3 also doesn't want this, because it doesn't want to collect that information about you, because information it doesn't collect is information that can never be leaked or stolen. Learn how to search or perish.
Asking for a downvote button. Again, it's not social media, this isn't reddit, you don't need to downvote a fic you don't like, you can just backbutton away. There's no algorithm so you would just be using it to be a dick to the person who posted that work.
Also, don't combine your shorter works into one big work, this is also deeply annoying. It prevents people from finding works accurately, because if they're searching for a work over 5k and instead they find your collection of 50 drabbles posted as chapters of one big work, that's worse than useless to them. If your hugeass one drabble-per-chapter work has one chapter with the tag I want, I'm not going to sift through to find which chapter it is. Just post your works as individual works if they're actually individual works, no matter how short.
snowghoul
prguitarman
origamiaround
discoholicmusic
izzy806
theartofmadeline
yousharknotpass
kianamaiart
germansingergirl
2087
