Nice to hear from someone who gets it! 🙂
And it reminds me that a lot of people seeing that interface are assuming that a read-only attribute is the same as read-only permissions. As I'm sure you know, even if the folder attribute were set to read-only (and we know it isn't) it would have no effect on whether you could save, delete, or change files within the folder. It only controls whether you get an "access denied" message when you try to delete the folder at a command line. It doesn't even cause any warning in Explorer.
It's a shame that users waste so much time barking up the wrong tree when they see this interface instead of looking at things that really could matter, such as the ownership and permissions on the folder or a problem with the application etc. If their files are getting into a read-only state we'd like to focus on what's causing that and not get distracted by this non-issue.
Thanks to Microsoft for devising one of the most misleading interfaces ever and sticking with it for decades!