Fair enough — didn't realise it had already been tried and it wasn't working without reward. That's not mentioned in the article but does make sense.

There's still a good argument for sci-hub to stay fully non-commercial. Let's see where it goes.

It's not clear if Sci-Hub themselves stand to make any money from this. If they do, the worst that can happen is that their incentives are distorted from being a highly-regarded community resource to maximising the number of manual uploads.