Well, Batman is like the worst example lol. He's anywhere from gathered by untrained thugs to wiping out scores of ninja. And that also goes for his character: the original monster men story saw him murder the beasts by gun while they slept, in the remake he utterly abhors guns and instead took them out in close quarters. He's between being a complete goofball and someone called out for never smiling. People enjoy the concept of him being "one" character but it's only a thing because the slickest and most popular writers invest time into each run to make it plausible. I don't even think Superman is so drastic even if the lines are more clearly drawn in the continuity sand.

As confusing as it is, the Legion did have one continuity until the 90s. The worst thing to me is that there were so many stories across random titles. I'm embarrassed to admit that one time I suggested the Legion had no place in Action 1000, when actually their feature ran right up to the issue before the start of my main bronze age stretch. Character wise they stayed pretty similar iirc and re enacted a few things, like Lightning Lad losing his arm. Their bond with Superman, well, instead of his legend they simply switched to beholding the man himself. Like the English language, all of this stuff was just lost to them intially. Sure Valor was retconned in and it makes things weird, but then hey, Valor's name came from Superman.

And then of course Levitz and Shooter restored the old Legion. But where change is involved, I have to say that bringing them back was actually a slight deviation: Johns has them soothe Clark's insecurity and helo make his heroic identity, where the original Legion made him insecure before he showed them up... as he was an established hero without them.

And many thanks.