Earlier quoted context omitted.
My understanding is that if you're offline, it skips this check and everything works fine. The reason this is a big deal is that the problem's on their end, so you're not offline, so it keeps trying and waiting instead of just letting you skip the check.
I experienced this a couple of weeks ago. My wifi was up, but my internetprovider was down. My Macbook came to a halt. Nothing worked anymore. The whole machine was extremely slow. When the internetprovider came back up again, everything was fine again.
Remembering the notarization problems people were having months ago I did some tests and confirmed.
Now have little snitch installed again and my laptops going to be an Apple orphan. So I never noticed this problem today by virtue of it pissing me off 2 days before.