I've also become more and more effective at quickly diagnosing problems and creating solutions taking into account the people, politics, tech, etc. involved. Tech is only one aspect of our jobs. A lot of time it's the easiest part.

Why would I stay this long at a job? I love the people in the dept I work in. The best team and job environment I've ever had. The drawback to staying a job this long is that, yes, you will probably be underpaid compared to market rate. Life is full of trade-offs and everyone will have to decide if it's worth it. For now, it is for me, but that might change in the future. If I get a new boss or the president of the org changes and he's terrible... /shrug maybe I'll move on. But life is short and if the position is good there's nothing wrong with staying IMHO.