Heretic of The Seventh Circle
It may be a skill, but it's simply not possible for them to know my game better than I do, so I'm the one who should be creating the house rules for it, not them. My skill at my game exceeds their skill at general game creation.
I don't like the one reaction a round, but I'm giving it more time before I change it. I MAY(I'm mulling it over) decide to give 2 reactions, no two of which can be the same kind of reaction, so not two opportunity attacks or no two spell reactions. I don't need a designer to come up with that. Nor do I need their expertise or playtesting to see how it affects my game.
Okay. That isn’t related to what I said, though.
They’re probably better at making broadly applicable rules changes than you are. Many people want a single houserule per “problem” that they can confidently apply to all their 5e games, regardless of what characters are being played.
Others aren’t as confident as you are in their ability to foresee unintended consequences of a rules change, or simply don’t want to have to change their houserule down the line. The dev team is better at that than most DMs.
It’s not a question of who knows a specific table better. It’s a question of who is more skilled at making rules that won’t create surprise problems down the line, and will work as intended most of the time, efficiently and without needing extra rules to manage the house rules.