Eh, I've played League since season 2, so you can understand why my viewpoint might be distorted :)
From my perspective it's much easier to get into LoL than it is PoE, but that's mostly b/c the first thing I do when I look at any game like PoE is look at the talent tree and PoE's talent system is kinda insane.
Leagues barrier to entry isn't as high as it used to be, but I agree it, like PoE, are not the most approachable games for someone completely green to the genre. There's also something to be said for age.. When I started playing League, I was 17, I was still in school and I could literally play nothing but games from sunrise til sundown.
These days I have much less tolerance for grinding or for high barriers to entry, so while I am now onboarded onto League, I don't think I could personally do that again for a different game