PoE will capture a few, but the game isn't accessible enough for a large migration of players, if on the other hand Diablo 4 isn't sorted out by next summer (season 4-5) then PoE 2 has a significant chance, even in beta. I believe the PoE2 developers already expect 7 digit numbers for players for beta (their current record is about 350k)
On the subject of PoE though, if you want to give it ago, just do it, when you open the passive tree, don't freak out, you literally have only 2 choices to start with and the rest is pretty self explanatory. Play through the campaign get a feel for the systems, what ever you do, do not try learn everything at once, your head will explode.