The overt camp was there from the beginning (same with the '89 Batman), but it wasn't as obvious back in the day. But as time passed the camp became evermore apparent.To me the Donner movies still work as well as ever anytime Christopher Reeve is on screen, but I admit they are starting to seem cheesier and cheesier with every passing year.
The '78 Donner film is fine until just after Superman's first appearance in Metropolis and then it starts to slide and never recovers throughout the rest of the films. The first film is tolerable overall, but it just doesn't work for me anymore as a whole.
That said John Williams' theme still sounds so definitive.
Those films both go very well with the spirit of the comics released during that era. I treat them in that context.