There is some good rock in the 2000's. Alter Bridge, Seether, Three Days Grace, Staind, Breaking Benjamin, Chevelle, Tantric, etc. I certainly can't defend what he's saying about older music though. The 90's had plenty of great Rock; The Red Hot Chili Peppers, The Offspring, Pearl Jam, Alice in Chains, Foo Fighters, Nirvana, Stone Temple Pilots, Tool, Days of the New, Creed, etc. And of course the earlier decades have some great Rock.
Why does everyone forget Weezer when looking back at 90’s rock? The Blue Album is one of the best albums of the decade.