Ageism in IT is very real. This is just one of the mechanisms by which it operates. The other side is the (youngest) programmers who haven't yet grown out of language fanboyism and dismiss your experience of last year's technology as irrelevant. Fortunately they're rarely in positions of hiring authority.
The IT industry takes about 10 years to cycle through fads. Someone I consider experienced has been through at least one cycle. I want people who can say XML? Oh yes, well I've never used XML but in the 90s I was doing EDI... (insert tech of choice)
At my previous company, where I began in the startup stage, we had lots of people older than 40 and 50 in IT. We had a QA guy who had to be at least 60. I suppose it all depends on the company (and probably the geographic subculture) but this "ageism" stuff is out of my experience -- I'll hire someone who knows what he's doing and is motivated to do it, period. Stupid shit like "but he has a wrinkle" is moot.
You may get asked, "so you never thought about management?". But you can rehearse a response to that. It's like the one about when you've been in a difficult situation. Example, "In a way I was managing" - you worked on this project, planned it this way, made these decisions. Or you could describe aspects you liked about the pace or type of work you were doing. Talk about the problems that would have been easier if you had been leading strategy, and about the mechanisms you instead had to use to influence strategy, and the reason why the tradeoff worked for you better than if you'd been managing. Use the question as an opportunity to highlight particular technical skills that you brought to the team and mention the rule of comparative advantage.
A great thing about IT is that the tools are so cheap now that anyone who wants to prove themselves can run a home project at virtually no cost to demonstrate their strengths.