Yes, I think that is a risk in the absence of a true "Proof of Deletion". Perhaps though it would be so expensive to maintain a copy of all this data that no o

Yes, I think that is a risk in the absence of a true "Proof of Deletion". Perhaps though it would be so expensive to maintain a copy of all this data that no one is paying you for that nodes would be incentivized to just perform the actual deletion, since the rewards of keeping the data are unknown and the time horizon for maintaining that data at your own expense is unknown.