Unfortunately, it's people like Sontag who - thanks to the NY Times- tended to define NY intellectual circles.
I've never read a damned thing she wrote.
I don't know if I'm better or worse, but frankly, I haven't noticed a difference.
About the only thing I can say is I've know extremely pretentious people who knew her who sang her praises. That ain't an endorsement, and I'm sorry to say, I can't form an opinion either way. But I hope when I'm dead my legacy isn't pretentious people who vex others at parties singing my praises.
On update, though, I should say, that certainly in this case, the enemy of our enemy is our friend.
What the fascists -there's no other word for it- tried to do in silencing this woman, despite her obscurity- is reprehensible, and she was right to speak out against the enemies of freedom running this country.