I find that type of stuff believable from Valve because that was their thing with Half Life 2. Here's a game where a ton of objects and ragdolls react accordingly, where physics are an actual thing, and no other developer tried to top that concept in a FPS. The closest example would be Rockstar with how bodies/ragdolls react, even then, what Valve did with Half Life 2 didn't influence game developers when it comes to what their engine did versus other engines.
While Half Life 2 is an excellent game, the Source engine was the real takeaway. Not with big developers, but with the modding community and what work Valve would outsource. You got CS Source, Gmod, countless mods, TF2, DOTA 2, Left 4 Dead, Portal, all out of one engine. No other engine has gotten as much community support than Source.
If Valve can demonstrate Source 2 in lavish ways, or in ways that make the modding community and other developers drool, another Source cycle of support is born. Half Life 2 was a delivery method for Source, Half Life 3 or whatever they release next being the next delivery method isn't far fetched.
DOTA 2 uses Source 2.0, but that seemed like a test to see how easy it is to port existing Source games to Source 2.0.
