If the files are exact copies, then MD5 checks will catch them; tweaking so many files just to bypass this could prove to be too tedious of a process for people to bother exploiting it.
However, people could create scripts for others to mass-download, -edit, and -upload their files accordingly to reduce this tedium.
How do you differentiate old from new? I can just create a fresh copy of whatever I’m storing and it’ll look new.
If the files are exact copies, then MD5 checks will catch them; tweaking so many files just to bypass this could prove to be too tedious of a process for people to bother exploiting it.
However, people could create scripts for others to mass-download, -edit, and -upload their files accordingly to reduce this tedium.
That can be trivially defeated.