Never understood the appeal honestly.

Same here. I spent about 30 minutes trying to play one (DoTA I think?) and figured out:

• Each hero has a zillion upgrades and abilities
• Each hero is basically on their own roguelite style upgrade path
• The game has a dozen or more such heroes
• icons and text too small to play on livingroom TV, controller play out of the question
• at mercy of online match-making algorithm if I'm not in a league/clan/whatever

From this I could deduce:

• There's no way in hell this is perfectly balanced - too many variables, it may as well be MttG
• Going to take 20 or more hours to dial in a personal play style
• Going to take probably 50-100 to develop a play style that can adapt to most situations
• League play will probably kick my ass, requiring another 50-100 hours of practice/training
• Causal play is out; likely can't pick up and play immediately due to lobby, variable match times

I'm not knocking the genre as a whole, but this is not for me. It's too far outside my typical mode of gaming and is likely to just frustrate me more than anything else. I'm familiar with hard to play online games like Quake, TF2, and even Soldat. But those have small power systems that, even with gross imbalances, were still playable because there were usually only one or two scenarios you couldn't overcome. Adding more on every axis just sounds like a wildly unbalanced system where the skill curve isn't steep enough, costing a lot of time invested in bad strategies before you figure it all out.