D&D Playtester for WoTC since 2012
I'd be curious to know what's the probability to get at least one score below 8 when rolling?
Other classes benefit less even with the same stats.
Sure, but that is not really relevant to the discussion. A Monk with high rolls has no "problem" in the game.
If you can play a 27 point buy fighter without problem, you can play a 30 point buy-equivalent Monk without a problem. The fact that a 30 point-buy fighter or a 22 point-buy Wizard would be even more powerful than said Monk is not really relevant to that.
What you roll on abilities is what drives what classes are viable and further defines where a certain class would be ranked in terms of others at the table. High ability rolls will absolutely make up for class, race and subclass weaknesses or to put it another way, class, subclass and race strengths can almost always more than make up for low ability rolls.
Now certainly playing the most powerful class with the highest rolls will necessarily put such characters ahead of everyone else at the table, but I don't see many players who design characters that way.
Sure. Sure. But the moment Bob rolls low, and suicides the PC, he pays me $1k, and $500 each of the players.
In 5E, this is my experience as well and what I see from most other experienced players.If dice rolling us used and I roll really well I'll usually pick a weaker class that interests me.
No one had played a Monk yet (2015/16 maybe) and didn't really know how to run one.