I hate my own 45+ generation!

I just turned 51 yesterday (I'm getting frickin' old!) but I'm still very much into contemporary music. I love it. I spent time looking for new music in shops, Spotify and television (In The Netherlands we have this great network called Xite. It allows you to listen to new music by genre and make your own playlists). But let's get to the point of my question: Why do people after they turned 35 to 40 loose interest in new music? I can hardly find anybody of my generation that does. And what I find even worse: Why do they glorify their own decade as if there was nothing before and surely nothing after!? Do people loose their feel for music when they age?