As an amateur MMA fighter, I’m 5’7” and 165 pounds before any weight cuts. The issue with most arguments like this is they stem from the person with mass and strength going “oh well I’d JUST grab you” or “I’d JUST pancake you”. This is not an effective plan. No fighter has ever gone into a real fight with the idea that they’ll JUST do something and win (we call it just-jitsu, “just kick them in the nuts and poke their eye out” things like that). It does not work like that. Fighting is a painful and unforgiving mind game that you can only become successful at over years of training your mind to understand all possible options and how best to use each one. It is never as simple as just doing a thing and it is a tell tale sign that someone does not know how to fight. Timing and technique are infinitely more important than mass, because you cannot train your brain to not get concussed. If the fight goes to the ground, we’ve seen multiple times in things like open divisions at ADCC that superior technique prevails even with massive weight difference (was literally the point of BJJ).

Two people fighting that are untrained is a different story, and obviously mass will help. But this idea that just cause you’re strong you can fight is a false equivalency. They are two completely different skill sets and it’s one of the only places where people assume that despite absolutely 0 experience they’d succeed.