Do people actually buy into it - since if the returns were good why would they sell the software? Is there any public and verifiable evidence that it produces returns that outperform the market?
because a bot can do tasks or strategies consistently without emotions

if you have found and implemented good trading strategy on a bot, you could have steady profits in the long run
if you do it by hands, you (human)

would have second thoughts and mood swings which resulted inconsistency
and would likely to deviate from original strategy that leads to unexpected outcomes