The way I interpret the best practices part, that this is just a little bit of advice.
Like you can still make a lot of interaction in a panel extension, and it is not smart because no one ever scrolls down to the about page to see it.
And you can make an informative component extension, and everyone will think it’s annoying because once they have read it, it has no further use while taking a very prominent space on the stream.
I understand the confusion is there because it’s a policy segment update, but I don’t think they are intended best practices to become strict rules.