Agreed; he pretty much lost it when W was elected and re-elected.
His hatred consumed him.
I remeber seeing his daytime show on NBC. I remember when they moved him to after Carson. Those were probably his best days. When he was an amiable host who knew how to make college kids laugh and he was pretty much the only thing on after midnight.
He was a lack-luster college student who wanted to make it in TV and hit upon adding funny asides to his weather-forecast segments on local TV as his first step on the road to recognition and stardom. Eventually, after making it big, he set up a scholarship program for students who maintained a C-average in college.
But, yeah, eventually he became unwatchable because he and his network came to the unspoken agreement that only half of his potential audience were worth the trouble of entertaining. David Letterman became an establishment toady for the Left and a mean man besides.
Long before he went off the rails, you could see the prickly, snarky host emerge that would have a guest on as much to insult them as to interview them. He started being hard to watch then. It definitely wasn’t the fun-loving David Letterman I grew up with.
The part I can’t figure out is why so many other late-night hosts had to follow in his unnecessarily snarky and overt, politically-biased schtick.