Well, it appears there are a few different types of copyright strikes. I've also seen strikes that did not disable monetization or longer video length, even when two were issued, but I've seen one strike that shuts down channel completely (no monetization, no 15m+ videos, no unlisted option etc). I'm surprised there's no more clarification from YouTube on this subject.
But this new system, if we can call it like that, seems to be bugged - strike is clearly issued on a channel, since monetization is disabled, but it's not shown on the overview page.