I don't think they really feel old, but very 2000s do have a dated nostalic. Nonetheless I think 1998 to Present is still pretty modern. Obviously technology has changed..
I didn't find out about Bronies until 2011 so I don't associate them with the 2000s. And the 2000s did have it's dress style and musical sound. Those stupid baggy pants for example >.< And the emo/scene style.
Obviously technology has changed..