This pretty much. All Diablo games suffer from the exact same problem and that is no meaningful endgame.
You get better gear, turn the difficulty up, get better gear, turn the difficulty up, get better gear, turn the difficulty up and so on. The big problem is that difficulty 1 is the same shit as difficulty 10000, with only higher numbers, so there's little to no point to keep going. D2 at least had the resistances and stuff which made it a little different.
D:I had a chance because it has PvP, but since the P2W elements are not disabled in PvP it's just pure shit. Like wtf is the point to pvp if the biggest factor to success is which team spent the most money?