It depends on the time too.
With a 1/0 game, Kasparov would win easily. The 2000 Elo would be completely crushed.
With a long game (40 moves in two hours, then 1 hour k.o., for example), it could be different : the 2000 should try to exchange as many pieces as possible, and then he should win. But it will be very complicated.
Hugh. I said.
I'm 2170 USCF and I suspect I'd probably lose such a match to Kasparov.