I often remove or edit the autogenerated section comment, e.g. when I am actually deleting the section, or inserting another section above it, or editing the last section in an article to tweak the navboxes.

In T178159#3683978, @matmarex wrote:

I often remove or edit the autogenerated section comment, e.g. when I am actually deleting the section, or inserting another section above it, or editing the last section in an article to tweak the navboxes.

Interesting use case. I did not consider that.
When deleting the entire section, I guess the autogenerated section comment should be left and appended with "Remove section".

When inserting a section one ought to use the Edit page button instead of edit the section, also when inserting navboxes at the bottom. But I guess different people use MediaWiki in different ways and this would break their way of interaction.

This definitely needs to be taken into consideration. Perhaps your use cuse breaks my entire proposal.

Anyone have any feedback?

In T178159#3684012, @Frap wrote:

When inserting a section one ought to use the Edit page button instead of edit the section, also when inserting navboxes at the bottom. But I guess different people use MediaWiki in different ways and this would break their way of interaction.

Too many users use edit section button when they actually add a new section. Then there is a wrong section name in edit summary. It's frustrating when you see this kind of behavior on a page you're watching, when you think someone has edited the section you're interested of.

In T178159#3684012, @Frap wrote:

This definitely needs to be taken into consideration. Perhaps your use cuse breaks my entire proposal.

Enforcing the section title might not be desirable, but you're definitely making a good point about browser autocompletion.

In T178159#3684098, @Stryn wrote:

Too many users use edit section button when they actually add a new section. Then there is a wrong section name in edit summary. It's frustrating when you see this kind of behavior on a page you're watching, when you think someone has edited the section you're interested of.

There's actually a separate (super old) task about this, T22307: Generate automatic summary /* blah */ when I manually add a section heading when editing. I have a patch pending for that, but it seems to have gotten a bit stalled.

On certain websites such as GitHub there is a text entry field that is prepopulated but empty so that when you press backspace then it removes the prepopulated thing.

https://github.com/mediawiki
Click on the bar at the top in the menu. Where it says "This organization" and "Search". In the "Search" field press backspace and notice how "This organization gets erased.

This could be a cool solution.

In T178159#3684012, @Frap wrote:

When inserting a section one ought to use the Edit page button instead of edit the section, …
Anyone have any feedback?

At time of writing this, there is no longer any edit page button on mobile. And the section-name part of the edit summary is not just enforced, but is invisible. If I want to add a section, I have to switch to desktop view or leave an incorrect edit summary.

See, for example:

We recently disabled the ability to edit the whole article by clicking on the top-most edit pencil. … T232170

In T178159#3684012, @Frap wrote:

when inserting navboxes at the bottom

What would be cool is a section break that doesn't display as a heading, but does show an edit link. It would still need a name for use as a link anchor and in edit summaries. For example, before a navbox could be a break called [Navigation]. If the mechanism was flexible, then each wiki community could arrive at their own naming convention. Open question as to whether it should be listed in the TOC.