what you’re missing is: every time someone says that, they’re saying your style is so clean and smooth, that it must be ai.
PLUS, i wouldn’t be surprised if “ai artists” are now lashing out against actual artists, not to mention: don’t feed the trolls.

have you ever met a compulsive liar in person? they have keyboards.
trolls online are actually mostly sociopaths, and they comment 95x more than regular people, and under many different accounts… when you reply and get upset enough, you become what they would call a “lol cow”, aka, a sensitive genuine human… maybe quit under this name, but don’t quit posting.
provide sufficient proof, and simply don’t engage with ai claimants afterwards. if a mod of a sub or someone with reputation requests proof, politely provide it, ignore all other haters and they’ll move on…

for a troll, a sociopath, it’s all about control. they’re controlling you to get upset, to go to great lengths to prove yourself… they’ll keep on insisting on more proof… frustrating you… and will never say sorry.

some people are real and doing the knee-jerk reaction to constant AI spam… but just don’t worry too much about it, provide reasonable proof once… maybe in a standard way each time you post, and just be a “grey rock” after that… responding only to mods and people with a really good history. (trolls really hate it when you check out their comment history)

really i would say this is an example of “concern trolling”… a tactic of pretending like they’re really concerned about some moral thing, and unreasonably accuse you of being immoral, so you feel compelled to defend yourself… and maybe they can get you flustered and banned….
p.s. do some stop-motion video of you making them.