I'm ... late 40s. Have been paid for working on software development in some capacity for... 28 years (first paid contract was 1993), and did hobby/amateur for several years before that.

I'm contracting with a couple different companies, and one of them... the others on the team range from ... 27-32. So... I've been doing professional/paid development work longer than most of them have been alive, certainly longer than any of them have been adults. The manager(s) I interact with - one just turned 31, and one is... I think 29 or 30.

The older you get the more common this may become.