LoL I remember in the early 2010s a porn comic that actually did this and people were shocked because it seemed like a lot of work for a small niche thing.
And then we realized that converting to a png and then back to jpg killed the identifier. But the system was in place and I have seen so many versions of and workarounds for it. Someone even had a custom clipper software that just looked for the excess identifier data on the end of the file and would trim it.
I think it’s wise to always think they might be doing this kind of stuff, especially big companies, but breaking it is pretty easy usually even by accident.