They claim they will only release when the game has something innovative to offer.

But then why release Alyx as VR instead of HL3? What innovation did HL2 episodes 1 and 3 offer? Why are Valve releasing virtual card games today?

Half Life as a franchise is great. Gabe was right to start nearly from scratch on HL1 back in the day. But now, they've got everything they want so the hunger is gone.