Redis becoming non free is something I expected. Those commercial projects with "permissive licenses", tend to do the same. I don't think "permissive licenses" are devils but I think most companies are devils.
I don't think copyleft licenses solve everything, because it's still possible to turn a project into proprietary crap but it's more difficult to do so. When I choose a software to use I always prioritize if it's libre first and then I prioritize copyleft licenses and community driven ones