People tell me to get out and I do, tried surfing for example, didn't really appeal to me. Tried dancing, same. Did lots of traveling but it's not so fun alone for a 50 yr old guy.
I mostly feel now it's partly about luck as well. Meeting the right people, having the right support groups is invaluable. Pretty much everyone I meet that I might work with though is just looking for cheap labor as "I have this idea, you're an engineer, how about you do all the work for free and I'll take all the money if we make any" or at least that's how it feels.
As for as whether or not 52 is old sure it's not as old as 70 or 90 but ... society in general labels me as old. Various forms require an age listed and 45+ or 50+ is the last group. HN tells me I'd have trouble being hired. Not yet my experience but certainly on my mind. Going to almost any bar, club, meetup, hackathon and I'm the oldest one there.
I don't feel I've lost my ambition. If I had then maybe I'd be content. Rather I just lost direction and belonging.