My .02 cents: Freely available and well operating NOW doesn't mean it will stay that way next year or the years after that. I can remember plenty of websites and software packages that started out as free, but had to switch to subscription, or pay-for-use, models to keep the lights on and the programs running.
And what happens if somebody contributes something in 2020, sees changes to the operation in 2021, and then decides to remove their contribution in 2022? Would that be possible? Legal? Could intervening users be threatened with a fee to keep what they printed with someone else's files? And how much of any of these answers depends on Thingverse policies?
So, is it even worth .02 cents?