I agree, and in aggregate it becomes a serious issue for the platform. People who buy autonomously are going to argue personally when it fails in any way.

I'm not sure how they would intend to stop it with this policy anyway. It at best is going to be an arms race detecting them. What it does do is prevent upfront the ham handed excuse of "I didn't bid on this, my bot did".

I wager the scammer industry looking for active bots and exploiting them would thrive. Automate creation of fake listings using throwaway accounts using popular keywords and arbitraging price lower and lower, and until automatic buyers start bidding, remember the price and delete listing. Recreate listing with that price from a separate account selling bricks for 600$, and voila - free money.