That could be also. But how do you confirm the legitimation of the file? I'm asking because I'm not sure if there is an easy way, like a HASH checking and something that can support it for validation.
From a logistical perspective, an arbitrary and every increasing number of documents tied to a single blockchain sounds like it'll create a chain that is unfathomably hard to work with. It'll eat up all the hard drive space you'll have available.
That's not the point. You can't stop digital files for being generated or even put nft. But the origin of them would be needed (sadly, forced) be validated against a trusted source.