I don't see why that's a problem? If you've created and released better software, why wouldn't you want your users to update?
The Bitcoin Core developers want users to update at their own pace whenever they feel comfortable updating. This is because new versions may contain consensus changes that users may not agree with, possible security considerations that users are not comfortable with, etc. By using an alert system to inform people about new versions, we would be pressuring users to update and we do not want to do that as that violates the principle of letting users upgrade whenever they feel comfortable with the changes.
I see what you're saying, but I'm still not convinced and am going to remain in disagreement. (That's okay, can't agree on everything.)
My perspective is that you're painting yourselves into a corner where updates will not be realistically feasible. People simply won't update in such a system. Stagnation seems to be an inevitable consequence.
I also feel like the concerns could be addressed with some
lateral thinking. If the concerns are:
* Users update at their own pace
* Users have security considerations with updates
* Users disagree with changes
Why not have an informative window prior to installation of the update? Explaining these very things, with something like a quick executive summary:
This update contains XXXXX, some users may not wish to update, **you do not need to update**.
If you do not agree you are welcome to continue using the previous version.
Please click cancel and continue using your current client
To add to that, why not have a system where the alert can be dismissed, i.e. "Alert: New version blah blah, click here for info" and have a button "never show again".
Seems like those two simple things would solve the concerns?