I think the lesson here is that people should stop just thinking of Valve as just a games company. And as has been noted below, dota is an insane money maker. Add to that, tf2 is now self funded through people making virtual hats. This isn't the signs of a company sitting on its laurels.
Can Valve make the next episode of Half Life as well as Naughty Dog might? Probably not. I can understand where you're coming from, but still think that if you look at the pile of games they've made, add in steam, the f2p systems they're developing and moonshots like the steambox etc, you find a company both involved and agile, not slow and monolithic. But that's just, like, my opinion!
Can Valve make the next episode of Half Life as well as Naughty Dog might? Probably not. I can understand where you're coming from, but still think that if you look at the pile of games they've made, add in steam, the f2p systems they're developing and moonshots like the steambox etc, you find a company both involved and agile, not slow and monolithic. But that's just, like, my opinion!