In looking over what some of my (former) computer networking colleagues and peers have done, especially after they reach their mid-thirties or so, it seems several reach a similar point that I did. However, instead of looking for non-computer networking positions, they forego work, and either look for computer networking positions or strike out on their own somehow.
I don't know a lot about these people's financial situations. Some have spouses or partners who can support them financially while they look for something else or start their own businesses. Some held stock in places that IPOed or were otherwise sold, so they had some money to live off of while looking for the next thing. But I don't know enough about how they were doing financially at the time of having to make a change to make a comparison to my current situation.
When I first joined AltaVista (the business unit) in 1996, a guy I worked with on the firewall project that ran out of money decided to leave Digital and try to find a computer networking job. He didn't think AltaVista was a good fit for him, career-wise, because it didn't offer the possibility of network software development. At the time, I didn't feel comfortable doing something like that because I had a lot less money saved up, not much in the way of 401k or pension, and some concerns about how long it might be before I might find something else. I rationalized the decision to stay on the grounds that search engines were "new" and seemed to be attracting a lot of interest (and money). I figured, maybe if I get in on the ground floor, I'll do all right financially in a stock sale or some other offering. Also, the possibility of building upon something that was in its infancy might open up other types of possibilities even if there was no offering.
With that I mind, I was thinking about some other IETF Areas such as Security. I never participated in that Area, and did only a small project that used results from it. In general, I feel more comfortable in the Transport Area. I sometimes wonder why I feel this way. There are some areas of overlap between the two, and there are some things I like about the Security Area, such as the algebra that's used in cryptography (although I don't remember much of it). But when I started working on things outside of the Transport Area, I couldn't keep up with new initiatives within it, which really bothered me. I wish there were more overlap between all the IETF Areas so it would be easier to move freely between them and not have to review lots of information just to catch up.