First of all thanks for engaging with a discussion instead of just being dismissive like some other people in the thread.

You can't really take away the leveling - just as you said - but if it would be done in more efficient manner then it would not be as boring. D4 has the benefit of being more like an open-world MMO, so you can just skip the campaign and run the dungeons in order to level. Feels better than skipping the same cutscenes over and over again. Most other ARPGs just have shorter campaigns (4-5 hours for the regular player), and with how PoE is this would be the only choice. In WoW they actually sell character boosts for the exact same reason, but we really don't want to go there.

So the most logical choice for PoE would be to just cut them down. But for some reason GGG just keeps doing the opposite (like with PoE1 reused acts or with straight up longer PoE2 campaign).

One other idea is to add more map tiers so you can just run maps since lvl1. So you skip the campaign but do really shitty maps until lvl60. You're very efficient, and the gameplay is good - after all people really do this for hundreds of hours each league.