You could host your own instance (of PieFed, Mbin, Lemmy, Mastodon, Pixelfed, Loops, etc.) and then you'd simply be sending the user-agent info to yourself.
The situation is a bit similar to that for NSFW: if all content is not perfectly labeled, then is the tag worthwhile to exist at all?
And mods will abuse the system regardless - e.g. look at how often Lemmy.ml removes posts citing "rule 1", despite that rule never anywhere anyway in any language stating that you are not allowed to criticize (or not support strongly enough?) Russia, China, or North Korea (or perhaps soon adding the USA and Israel?). Regardless of platform - Reddit, Lemmy, PieFed, Mbin, nodeBB, Mastodon, Pixelfed, Loops, etc. - mods are gonna mod regardless, and some will be better at that task than others.
Though it is still useful to have "rules", and use them in communities, even if they aren't properly implemented in all situations. The alternative being 4chan where anything and everything goes - not everyone is looking for that?
I guarantee you that Lemmy has for multiple years already abused non-AI content in a far worse manner: see e.g. the (non-AI) moderation tool santabot. Even so, Lemmy does not abolish the ability to post things, or to vote on it. i.e. the worst excesses of a thing do not preclude good uses for it. Knowledge that Santabot exists may encourage you to stop participating in the entire Threadiverse, but it does not need to? Systemically, the Threadiverse is fairly good, overall?
And now PieFed offers tools to detect AI content. I guarantee you that it will be abused, somewhere/way/when/how. Though at least now it exists, and can be improved? And we can be a part of that process too, by offering realistic suggestions to the development team, which demonstrably listens to and actively solicits such feedback all the time.
What makes the thoughts strong is that their implementation already exists.
Likewise, PieFed saw a number of opportunities to improve things, and rather than simply wishing that something were so, people expended effort to actually code them up so as to make them REAL, i.e. no longer mere thoughts but actions.
e.g. Lemmy offers a marking/tagging for NSFW, which PieFed expanded so that NSFL (gore) is an entirely separate category. Theoretically I could completely hide all NSFL while blurring the thumbnail of NSFW posts, or vice versa, or make both sets semi-transparent, or whatever. The Lemmy software might offer thoughts and prayers along those lines - e.g. theoretically you could dedicate different communities for each type, or even different entire instances (one for NSFW and a separate instance for NSFL?), or perhaps add standardized keywords (not that Lemmy allows keyword filtering innately, as PieFed does, but in case some 3rd party apps wanted to do so?) to distinguish between NSFW vs. NSFL - but multiple years ago now PieFed birthed that thought into a full-blown solution.
In the same manner, PieFed is far beyond the stage of merely beginning to have a couple thoughts along the lines of dealing with AI content: as that linked posts indicates, 5 months ago it already offered a full implementation of a solution.
In short, just as NSFW/NSFL posts or bot accounts are totally fine so long as labeled, so too AI posts are fine... unless unlabeled as such. And if users refuse to label them, then community mods have tools that help them detect and label them for the users.
PieFed's options for AI content are:
Show
Hide completely
Label as AI
Make post semi-transparent
This method democratically puts powerful tools into the hands of end-users to individually choose what approach works best for them, rather than e.g. make an authoritive declaration such as defederation of instances that often allow AI content.
Still needs an instance owner who is legally responsible for all the content on the entire site - this way the police know who to come for if there is illegal content like CSAM. At that point, better make sure that the admins are trustworthy individuals who have been vetted more extensively than simply having applied.
But sounds a great way to engender a sense of ownership among mods (& perhaps those admins who were vetted).
Btw PieFed also has several features that implement democratization of moderation, lessening the work that a mod traditionally is forced to do on Lemmy since the end-users can do the thing on their own, aided with software. e.g. if someone wants to see less content about Musk or Trump, then keyword filters provide that option (All, Some, or None), rather than a moderator having to decide for all of the community members at once. Or if someone wants to avoid contentious content, they can hide or just collapse (requiring an extra click to read) comments below a certain (user-definable) score threshold. Or NSFW content can be blurred, rather than simply allowed vs. removed; also NSFW is distinguished from NSFL (gore). Also fwiw, moderator reports federate, and someone is actually notified if their content is removed or if they are banned, plus much more - PieFed already allows much more democratic processes than the more authoritarian-styled Lemmy provides for (I believe there is even a deeper description of administrative roles built right in). So you may want to read about that. See also this article.
However it is accomplished, it sounds like a grand experiment!
You could host your own instance (of PieFed, Mbin, Lemmy, Mastodon, Pixelfed, Loops, etc.) and then you'd simply be sending the user-agent info to yourself.