I never thought people would be looking at the 2000's through rose colored glasses. The 2000's were a silver age at best. Let's see here...
George W Bush in office
Paying like $4 a gallon for regular fuel at the pump like 15 years ago
6XL tall tees and wearing size 46 jeans when you were a size 28
Sharp decline in the quality of music
Ringtone Rap
The rise of hipsters
The rise of gentrification
MySpace
Facebook
Flip phones
Horrible movies that were cultural memes (I.e. Napoleon Dynamite)
The introduction of text messages and the beginning of textual relationships
Everyone going into obscene debt to go to college for a worthless "education" and not being able to find a job afterwards (especially post 2007) while looking down on tradespeople
Nelly
So as we can see here, the 2000's weren't that great. But neither were the 90's (I.e. Sky high crime in every hood in America, baggy ass clothes, depressing ass dark mid 90's reality rap from all coasts, dial up internet etc.). People just have a bad habit of lionizing the decade when they went from a child to an older teenager.