The problem is that the error conditions are relatively rare. Most of the time it doesn’t break anything. So even with dogfooding you can miss it or not see it

The problem is that the error conditions are relatively rare. Most of the time it doesn’t break anything. So even with dogfooding you can miss it or not see it as a problem early on. But after 10 years of evidence that it was a mistake, that it’s almost never intended, and the fix won’t break much if anything, it’s time to fix it.