It’s possible that MrDrNose already had UE4 before the release of UE5, and didn’t want to switch over/lean the new engine (not sure how different UE5 is from 4, as I’m not a developer myself).
Well, from what I’ve seen, it’s harder. That’s also from experience. I’m saying that I never actually had UE4, but I’ve seen snippets of it. UE5 is the one I’ve used, and well it’s a bit harder. Blueprints are way harder, that’s for sure.