I think the films can definitely square up.

ROTJ Luke learns how to be a Jedi, makes his Jedi academy to work as he sees fit. Doesn’t even read the Jedi Texts. This much we can deduce.

Snoke comes along, creates the FO by rekindling the ashes of the Empire. Starts working his influence over Lukes pupils. Where does Snoke come from? We likely know as much as the characters do.

Luke notices something odd in Ben, he reaches out and feels the dark side, the emperor, vader, everything he fought in the past but stronger than he ever encounterd. He freaks out, grabs his lightsaber. Why? because fear leads to hate ect ect. Its a moment of weakness where he lets his guard down and let the darkside drive his actions (and if you think this is out of character, you need to rewatch ROTJ, fear is exactly what makes hm go a darkside against his father).

So after making a catastrophic mistake he flies to the island and becomes a recluse, realising that his own ways were not good enough to fight the dark side. Just like Yoda and Obi-wan. Not making much attempt to stop the Empire/FO on their own are they.

I really don’t see any conflict here, it all makes narrative sense to me.

If you’re looking for reasons why it doesn’t work then you’re going to have to go all the way back to 77 because the whole thing asks for a whopping great big heap of suspension of disbelieve to believe any of it.