What's the point if you can't update the OS and if you do you have to jailbreak it again, every time, until you reach a point where you device is not supported or there's no jailbreak available and you are back to the doorstop?

Unofficial Android builds are fully supported, maintained and updatable builds, they simply are not released by the phone vendor or Google.

If you can’t update it, the jailbreak is permanent, it’s again by the people as you describe.

> If you can’t update it

That's the original point

you can' update your phone, because it's not yours

If you're happy, good for you, but it's not ok.