During the 2yo season results can be dominated by horses that come to hand more quickly then others and results during the 3yo season as the crop matures should hold more sway. The business model in the U.S. doesn't favour older horses going to stud and most potential stud colts have pretty much left it all on the track as 3yos in pursuit of success in stakes races to ensure a place in the breeding barn. Those that return at 4 are pretty much racing free for all class and doing so after a tough 3 yo year and often struggle with the transition to open class.

If the business model was different and the horses managed for a lengthy career on the track then it's likely a number of them would have good results. One swallow doesn't make a summer, but Mr Feelgood was a stakes level ( won the jug) colt at 3, went to stud but had fertility problems and returned to racing. His downunder record as an older horse was pretty good.