Prusa had been moving towards proprietary licensing (if they release files at all) for a while now, due to their open source design files being used to undercut the original with cheaper clones.

I seriously doubt it's the undercutting that's the problem here. When they release a new model they can't keep up with demand anyway, they max out production capacity on legitimate orders.

I think, if anything, the problem is when people buy a cheap clone and blame Prusa when it fails.

This is why we can't have nice things