Have you tried any of the open source game engines? Bevy? Godot? They're not as intimidating as UE5.

I like to write engines, not to use one of them, ther eis something inside every human being, when we see somethign we like, we want to be part of it, recreate it, personally i do not see any fun in using an engine, i did not do, i do not see satisfaction in it.

Same for me, tbh. I see two problems with state of the art engines:
I want to use my custom tech of realtime GI and LOD, and i want to use the physics engine of my choice. At this point it's easier to write my own game engine than hacking an existing one to enable this.
State of the art won't give us new games, and that's what we really need as current games seem stuck and disappointing. Usually new games come from new technology, and my bet is replacing animation with robotics simulation.
Engines do not even get IK right.