Likely, they don't really care to stop it. Real people still use it enough that the advertisers don't really mind.
I'd suppose that they cannot really tell the difference between a bot and a real person, at least at scale.
I follow a few non-English speaking hashtags that act as local news sources for their areas. These hashtags have been active for a few years. Though Twitter has a lot of policies for English twitter, these languages really have no policies. By that I mean they live-stream executions, have drug sales, solicit sex-work, etc. Illegal isn't really a thing in these places to begin with. That said, these cases are somewhat rare and these hashtags are mostly used as genuine news sources. Granted, these are 'edge case' languages, but still, it's a free for all that Twitter doesn't care to dive into.
Based on the 'extreme' cases and their long lived incoherence to Twitter policy, it's not hard to conclude that Twitter really does not care to enforce policies unless forced to.
I'd suppose that they cannot really tell the difference between a bot and a real person, at least at scale.
I follow a few non-English speaking hashtags that act as local news sources for their areas. These hashtags have been active for a few years. Though Twitter has a lot of policies for English twitter, these languages really have no policies. By that I mean they live-stream executions, have drug sales, solicit sex-work, etc. Illegal isn't really a thing in these places to begin with. That said, these cases are somewhat rare and these hashtags are mostly used as genuine news sources. Granted, these are 'edge case' languages, but still, it's a free for all that Twitter doesn't care to dive into.
Based on the 'extreme' cases and their long lived incoherence to Twitter policy, it's not hard to conclude that Twitter really does not care to enforce policies unless forced to.