Personally, I do not have any automatism to detect LLMs larping as people. But I do review accounts that follow or interact with mine, and if I find any that are bots, I’ll enact counter measures. That may involve reporting them to their server admin (most instances don’t take kindly to such bots), blocking their entire instance, or in extreme cases, start serving them garbage interactions.
If any of those end up interacting with me, or I otherwise see them on my timeline, they’ll get treated appropriately: reported, blocked, or in extreme cases, served garbage interactions to. Serving garbage to 500+ bots is laughably easy. Every day I have over 5 million requests from various AI scrapers, from thousands of unique IP addresses, and I serve them garbage. It doesn’t make a blip on my tiny VPS: in just the past 24 hours, I served 5.2M requests from AI scrapers, from ~2100 unique IP addresses, using 60Mb memory and a mere 2.5 hours of CPU time. I can do that on a potato.
But first: they have to interact with me. As I am on a single-user instance, chances are, by the time any bot would get to try and spam me, a bigger server already had them reported and blocked (and I periodically review blocks from larger instances I trust, so there’s a good chance I’d block most bots before they have a chance of interacting with me).
This is not a fight bots can win.