It sounds to me like you just personally don't care about cinematography. Which is fine, but that makes it surprising to me you open with "I'm a film major", as if that means your view is the "correct" one and everyone else just doesn't know what they're talking about. I'd figure someone who studied film would care about things like this even if we're talking about an ostensibly "bad" TV show.
Really, I don't even care about Seinfeld in particular. I've never watched it and I never will, because it's not my type of show.
But this isn't about Seinfeld, and I'm not personally inconvenienced by this or angry about it. I'm saying this because it's just universally a bad idea to cut 4:3 content into 16:9, regardless of what it is. It could the lowest tier commercial garbage or Twin Peaks or anything in between. You will always make things look awkward, and the viewer will subconsciously notice. This goes even for shows that had poor framing to begin. And of course that's not even touching on the fact that, in this case, it actually just ruined a scene by making the most important part invisible.
And personally, I think it's not up to any individual to say "I consider this work to be unworthy of respect" and start messing around with it and diminishing the experience for the people that do care. Someone else might be deeply invested in something you consider completely unremarkable.
What's more, you'd have to expect that some TV shows will end up getting remastered, then cropped, and then the masters get lost before a proper release is ever done. Again, not talking about Seinfeld in particular, but you'd be amazed at how many modern works become lost media even today, and this sort of thing isn't helping.