I agree with a lot of what you said here. I'm still ok with Superman II because I was so glad to see Superman go up against super powered foes. This scenario was better realized in Snyder's Man of Steel, but for 1981, Superman II gave us a great super-fight. If you think about it, we never really had that before. Not in the George Reeves' series and not in the Superfriends cartoons where they wouldn't show punching. So, Superman actually getting physical at the level of Superman II was really a novelty in media adaptations!
However, like you, I also have felt that writers who profess to be Superman fans are really just Superman MOVIE fans and that's all they know of the character. So, for a lot of writers they want to bring back their childhood and keep Superman trapped in 1978. This is another reason why I loved Man of Steel so much. Snyder wasn't having that.
Media adaptations becoming so predominant in writers' minds was also evident in Allan Heinberg's Wonder Woman One Year Later arc after Infinite Crisis. He made Diana a non-superpowered identity, brought back the spinning change, and made her a government agent. And it seemed like he patted himself on the back for this! Again, bringing Wonder Woman back to 1977 is not a good way to show us how much you love and understand the character.
I know people loved Christopher Reeve and Lynda Carter from their childhoods, but we have to let go and let the characters stay current. I know Zack Snyder is polarizing, but he did give us Henry Cavill and Gal Gadot who both did great jobs and allowed the characters to move forward from their previous media incarnations.
Another thing I agree with you, and Jim Kelly, about is the quality of the tin case DVD set of the Superman movies. Over time, the surface of the discs has become damaged. It still might be partially playable, and sometimes you can work around it because when the playback skips over a damaged area, you can often rewind close to where you left off, but basically the damage to the disc surface is not fixable as it is "disc rot" rather than mere scratches. If your disc surface looks something like the below, forget it. Buy the Blu-Ray, which are better quality discs or better yet, see if there's digital copies of the movies on, say, Vudu that can be bought.
I was at first resistant to Hollywood's seeming desire to move us away from owning physical media and to make everything streaming digital copies, but over time I am seeing the wisdom in not having to warehouse physical media -- whether it be books, comics, cartridges, CDs, DVDs, Blu-Rays etc, that take up tons of space and can deteriorate over time -- and switch to digital copies that can be stored in the cloud. It takes getting used to, but there are lots of benefits to going all-digital, and I think that kids today are owning fewer and fewer things in a physical format, so it is the way of the future.