That's me, almost. 59 and riding moderately priced bikes with some bling because the bling is gone in my legs, but it's still fun to ride and look good doing it, even if I'm a lot slower than I was 40 years ago. My newest is a Serotta with Columbus tubing from early 90's. Still a sub-$1,000 bike but chicks at SAG stops are always commenting on my "lugs" lol

To answer OP's question ( and this thread did seem to get a bit hijacked) the higher the price the more aero/lighter/better components. It's those variables. The degree to which these variables change after the $3K mark is marginal - the curve flattens out pretty quickly.