Well, I got dozens of game design concepts put into PlanetSide 1, including how the world map interconnected, and wrote a miniaturized installer with 30,000+ downloads. (That was later copied by the Sony devs).
Also wrote a TRIBES 1 server modification with years of tournament play, about 40 servers running it, and about 20 teams playing.
And there’s a whole series of changes in Overwatch that a suspiciously similar to what I’ve suggested.
And yeah, I’ve been kinda slacking on Overwatch, but usually had been in high Plat and occasionally in Diamond.
(Been playing a lot of Smash Bros)
Either way, I think I could confidently say I know how the game is built better than most GM players who have zero game development experience.