Time reversal changes everything, not one event,
No. It only changes one event (Lois's death).
which added power to Jor-El's warning,
Jor-El's warning goes nowhere and does nothing. Superman's act of traveling back in time to save Lois has no negative consequences whatsoever.
In the original version, his saving Lois would inadvertently lead to the release of General Zod and company from the Phantom Zone, but that's not what actually happens in the film as released. As released, Jor-El's warning is just there to create a conflict between Superman's Human and Kryptonian sides which he resolves by both saving the world
and saving Lois.
Reeve-Superman acted for purely personal reasons--the polar opposite of the self-deceiving myth that this interpretation was some hyper-selfless Santa.
I mean, no one claimed he's a completely sefless Santa Claus who doesn't have some people he likes more than others. But
goddamn, would it kill the Cavill Superman to at least
try to act like he enjoys the company of anybody in the world other than Lois and his parents? To
smile a little at the people he's saving instead of acting like a burdened god? To show
concern for the people dying around him at the Capitol instead of just looking annoyed he has to save people again?
Further, his selfish obsession with Lois had him sacrifice his own heritage in Superman II--giving up his powers and that allegedly selfless dedication to protecting the world. Even if Zod and the Gang never landed on earth, the fact Reeve-Superman still gave up his power and heritage while a still-very troubled world needed him said it all about what he was not.
Sure, it's his Gethsemane moment. And then he realizes he must remain Superman and resumes his role, and even sacrifices the possibility of life with Lois.
Cavill-Superman made the ultimate sacrifice for all humankind,
No, he made the ultimate sacrifice for
Lois. His dialogue makes it very clear that she is his real motivation, not humanity.
Again, I just wish the Cavill Superman actually acted like he
liked people instead of merely tolerating them. Can you actually picture him hanging out with anybody other than Lois after work? Having any friends outside of Lois? 'Cos I can't.