When I was home sick in high school I made an eggdrop bot pretending to be a teenage girl in a webchatroom that was popular with kids (and creeps) at the time. It used simple regexes and pattern matching I gathered from logs with some randomization between predetermined phrases randomly combined with smileys, just replying to people that would cold-DM it.

After a couple of days, people would desperately go back and forth for upwards to an hour with it.

That's nothing compared to what current gen can do. People being more aware of bots being a thing in general these days isn't sufficient to compensate.