The article states a software update will be required to fix the store:

> can still accept these certificates until a future software update

This suggests they don't have the capability to patch it with Rapid Security Responses / Background Security Improvements, given that they haven't.

Sure, I speculate that they likely would have already if they could have. Sure, I speculate that if they couldn't have, they might add the capability for the future. Sure, I speculate about why they wouldn't have already had a process for this. Whatever whatever. Disregard all that if you want, but the fact remains in the article.