It's not analogous to a filter, because that's applied to the actual work. The model does not keep the work, so what it does isn't like applying a filter. It's more like being able to reproduce a version of the work from memory and what it learned from that work and others about the techniques involved in crafting it, e.g. art students doing reproductions.

And if OpenAI were selling the reproductions, that would be infringement. But that's not what's happening here. It's selling access to a system that can do countless things.