[oblio]

How much skill and expertise do you need, though?

In most fields of activity after 2-3-5 years you should you should be a reasonable journeyman and after 10 you should have a decent mastery of your field.

To me a term limit of 15-20 years should be more than enough.

[plebianRube]

Try changing jobs as a software dev after 10 years. Every 'good' company will put you through 3-4 coding challenges, treating you like your fresh out of college.

[oblio]

Yeah, but we're talking about public positions here (public office). High visibility into both the good and the bad that you do.

Hardly comparable with software development work which is generally completely out of sight and therefore hard to quantify or verify. And I say this as someone who's been through the whole interview dance a bunch of times.