Does the addon.json "require" key work?

I created addon.json to replace the about.php file in one of my apps.

It has the "require" key like so:

"require": {
  "vanilla": ">=2.5"
}

To test the version requirement, I set the value to >=2.6, but it still let me enable the app in Vanilla 2.5. We don't need to use this now, but it'd make a good bug report. Has this worked for anyone else?

On a related note, I haven't tested this yet, but does Vanilla 2.5 read only addon.json if both files exist? Additionally, if an admin hypothetically had installed app that works for 2.3 and upgraded the app to one that requires 2.5 while still being on 2.3, the old about.php won't prevent them from using the app, so it's up to the developer to make clear upgrade instructions and the admin to make sure they follow them accordingly since the addon.json file is pretty nice!