>they will never earn a single cent without investing.

This is far from the truth and I'm sure curie and other curation projects beg to differ. There aren't just "some exceptions", a big chunk of users start from scratch and earn their way up by being active.

>further, this will only encourage even more bots

There are good bots and bad bots, the bad ones often get countered by the good ones or users that notice them. The majority of users don't join and think "how can I create a bot for this?"