How else is he supposed react to not only a product that doesn't exist, but one that hasn't even been announced? Panic? People (not necessarily here) mocked Jeff Bezos when he dismissed the threat of the iPad and iBooks to his Kindle business. And guess what? A couple years into it and Bezos was right.
Furthermore, let's be honest with ourselves, Apple knows how to do R&D: fail as often as you succeed but when you win, win big. They have had notable failures. Look no further than, well, Apple TV. Their desktop business never got traction. iBooks is basically a failure. They screwed up the nano and backtracked. So their successes we all know about and think about, but they have felt what failure feels like too.
Now, maybe this new "doesn't exist thing" will change the world but maybe it won't. HDTV sales have completely stagnated in the US. Penetration is high and the need to upgrade a 4 year old 50" tv is small. I don't think an updated UI is the difference, nor is the ability to rent on demand.
As for DirecTV, I have it and enjoy it. I'm not married to it, but nothing about paying Apple's fees is particularly compelling. I get my free Amazon Prime Instant Video as well as the choice to rent stuff not free. And DTV has NFL Sunday Ticket, which is the bees knees for an out-of-town fan. I like FIOS too. I'd rather chew ground glass than go back to Comcast though.
For me to spend $1500 in replacement costs, it's going to have to be a whole lot more than widgets, streaming and a slick UI. YMMV.