I don’t really support that reasoning. Legally, as customer you get a license to use software under certain conditions. You don’t own it. It’s not yours to change and fix as you see fit unless the licensor specifically allows that—which is usually not the case for commercial proprietary software. Of course in the past, such things were never enforced. Providers on the Marketplace couldn’t even define their own licensing terms and the marketplace is so small, that no one bothers to fight legal battles over a single product, let alone a single sale. But this doesn’t change the legal foundation. I much rather see the marketplace get more professional and add more legal and technical protection of the uploads.
The discussion about abandoned resources is a little weird, since that has nothing to do with the IPS platform. It’s not just the same for every other software marketplace, it’s the same for every business which might suddenly fold. It’s up to every admin to weigh the risks of using third-party tools—or even the IPS apps for that matter, since apps and functionalities from IPS can also be removed at any time.