I've been shooting .45's since the early 70's, competitively for a number of those years. I would not argue a 9mm isn't easier to shoot. Just as a 9mm is easier to shoot than a .40. Given .40 and 9mm's similar performance levels, I'd carry a 9. It has nothing to do with being unable to handle a .40.
Recoil is a range issue. Anyone can train past it. I have seen 5' tall 100lb woman shooting 12 gauge slugs.
The dedication level is what is missing in today's young cops. The new generation of cops is not the same as it relates to gun handling. They could probably text in an order for a double latte while in a pursuit though.