[samatman]

Frequency isn't countable, so I'd parse that sentence as "Suggest tracks like this less often".

"Suggest fewer tracks like this" would also be a valid request, the point is that it's an ellipsis either way, so I don't see a problem.

That's before we get into the fact that the 'invalid' "Ten items or less" formulation has been frequent in English for hundreds of years...