I certainly don't like the idea of Steemit Inc using their SP to get involved by downvoting bot promoted content. I would rather community action against it. Considering the cost of downvotes, I see this as unlikely. @spaminator and @steemcleaners could include buying votes from multi bots as a form of abuse. High valued downvotes from these accounts would reduce the buying of votes very quickly.
Any action that puts an end to or greatly damages the profitability of bots should be met with an alternative form of income from stake. Higher curation rewards and possibly curation beneficiaries to delegators could help.