Suggestion

It's not just @JoshuaKGoldberg that does this.

All of our issue templates contain title placeholders for people to fill in, eg:

However pretty regularly we get people filing issues and:

1. forgetting to fill out the title entirely (eg Bug: [rule name here] <short description of the issue> #5650, Bug: <short description of the issue> #5994)
2. leaving the < behind (eg Enhancement: [array-type] <Option to only enforce array style for simple types> #6952, Bug: [no-floating-promises] <Promises must be awaited> #6766)

There aren't many examples floating around because usually we'll just silently fix things up for people. I personally opt for silently fixing them just because it wastes less time than me asking people to fix it before I respond to them.

Sadly GH issue templates don't have a "title wizard" to give us structured titles, or a "title validator" to prevent these cases.
So our only option is to either keep manually fixing it, or create a bot to comment and tag issues automatically.

Rough idea:

1. on create or update of an issue
2. validate the title
3. if title is invalid -> add the "invalid title" flag and comment calling out the problem
4. if title is valid -> remove the "invalid title" tag and hide the previous bot comment