I would bet you that Postgres insert and query performance is better overall if all names in your table are, say, up to 10KB long than if you have a bunch of bo

I would bet you that Postgres insert and query performance is better overall if all names in your table are, say, up to 10KB long than if you have a bunch of bots inserting 20MB-long "names". And 10GB long strings are just not supported by Postgres, at least with default settings. And the point of adding limitations on length is that you shouldn't even accept the HTTP request if it passes some size, as it will severely degrade performance if you allow someone to upload a 10GB string, even if you separate it into a human review area. Finally, if the legal requirements change and legal names can legitimately contain cryptographic material, than your system has to change. There is no point in designing a system that tries to work for any possible use case.