I used to get called a 10x developer, I was also called a rockstar and a ninja and a 100x dev and every other compliment that was hip. Then I hit 30. That type of talk stopped. Then I hit 40. Now I will not be considered for any entry level, mid level, or senior level software dev job anywhere in the United States, despite being very desperate and willing to relocate for anything. Doesn't matter. Too old. I'm suppose…
I can't say much personally, other than at 36 my career is still on an upward trajectory. I've worked 50-60 hours a week my whole career though, not for the company usually, but putting in time on side projects, learning new skills. I think part of the problem is once you have a family, priorities change and you don't have that kind of time to stay on top of the game anymore. That doesn't mean you can't compete, you have other advantages on the youngsters - you just need to play to your advantages.