What's more, the spec was agreed upon, in relatively public forums, with a voice from the community.
It was agreed upon and no one caught this issue. Now we know the issue.
There's nothing wrong with using a protocol you think is correct. There is something wrong with using a protocol you know is incorrect, but continue to use it anyway.
The entire internet should not be required from now to forever to workaround LE's mistake. LE should fix their protocol.
And worse, this protocol isn't even needed for LE. They could remove it, and everyone could use one of the two others that are secure, and LE would be just fine, and everyone -- even those crappy shared hosting providers -- would be perfectly secure.
LE created this issue all by itself, and is capable of fixing it all by itself. LE should do that.