u/Bananenbiervor4

Weight is someone an individual can impact. Your opponent is 125kg pure muscles? That‘s not „unfair“, that’s the result of hard training. If my opponents endurance is better than mine and l gas out that‘s okay, but if he is heavier than me that is unfair?
The height however is something you are born with. You are 2m tall, with 10cm more reach? That is indeed an unfair advantage that your opponent has no way to compensate.

On amateur level weight classes are okay, just to prevent injuries. On a professional level they are just out of place. We want to see the best a fighter can be, but then limit them with some stupid weight rules? Not to mention that weight cutting is super unhealthy. Let them decide for themself how much of their time they want to spend training martial arts and how much of that goes into muscle building. The results would even be more interesting, more telling how you get the very best out of a fighters potential.