That’s partially due to that fact that Roblox is a platform and is not a gaming company. It’s a different business model and culture that isn’t subject to the vagaries of the games industry.
(And yes, it’s a great place to work!)
(And yes, it’s a great place to work!)
But I see what you are saying. The model is very different from a typical game studio.
Valve and Epic both develop big titles in-house. Whereas Roblox’s experiences are developed by entirely separate entities.