[1] - https://cdn.cloudflare.steamstatic.com/apps/valve/Valve_NewE...
People try to poke holes in their ways, yet they have made legendary games, amazing hardware and absolutely dominate the game distribution market.
Basically all of their competitors use the traditional management style. What other evidence would you expect?
Going forward: Someone else created Counter Strike, someone else created DoTA, someone else created Portal, someone else created Team Fortress, someone else create Left 4 Dead. Valve took these projects on and polished them, but they didn't really create something new until Artifact - which failed in the market.
What you also don't see is all the unannounced projects that went nowhere, because that's what you get when people just get to play around on their own, indefinitely.
Most of them have their origin in community mods, some already having gained substantial traction on their own.
Maybe their ideas department isn't the greatest, but their execution on these games was very good in the long run. They popularized hats and make absurd amounts of money from it.
Let's not forget the Steam Deck. Early on still, but an excellent product in a whole different area.
A team created Narbacular Drop, and that same team then worked on Portal as part of Valve. It's not "someone else" by any stretch.
For instance, they have a round table where everyone would judge everyone else. So if too many people don't like you, the axe is coming. Sounds miserable.