Do you think I should move everything to the 1970s-1980s?
1977 - Superman: The Movie: Special Edition
1977 - Superman II
1982 - Superman Returns
1983 - Superman III
1983 - Supergirl
1985 - Superman IV: The Quest for Peace
1995 - Crisis on Infinite Earths
This might be a much better way to fit everything together. I don't think I saw anything in Crisis that makes it modern day. It could be like Earth-16, Earth-F or Earth-666, where a traveller to that universe ends up at a different point in time. Lex also states that Superman took 5 years of his life in Superman Returns: Prequel. If Superman II took place a couple months after the first film, that would fit better. A lot of the timeline evidence fits better overall if this reality was set in the 1970s or 1980s. For example, the technology, the arms race and the twin towers remain in tact. I'd have to ignore some newspapers in Superman Returns that are related to Superman Returns: Prequel, but I don't think that matters too much.
Though, more time between Superman Returns and the other films gives a bit more time for Lois and Richard to split. I suppose Jason could have a baby sitter, but they had no problem bringing him to the planet. Pahaps now he has powers to an extent because they stopped treating his "health issues", they feel they don't need to. My head-canon is that Richard has shared custody, he's still "technically" the father after all. No idea why he's not at the planet, but that's what retconing does. These films were never meant to fit together, but thankfully it's not impossible.
I do like a long gap of 10 years, though. Enough time for Clark or Superman to date, reveal their identity without using a mind wiping kiss, get married, and finally a remix of Kingdom Come to occur.
Edit:
Computers, so no, but at 1:30 is that a typewriter or am I seeing things? It's probably just a printer.
Although, 5 films vs 1 film + tv crossover. It's all a mess anyway, either decade works. Pahaps in this world of heroes, technology evolved faster due to their presence from 1977 onward. You can come up with whatever reason you want for Superman Returns, though.