I don't really care about their wording. The proposition that Google has made the choice that labels can either (1) join the premium service or (2) not be on YouTube anymore does not really seem disputed by anyone other than you. Except you may not even dispute it now? If you don't, you may very well not agree with the opinions and commentary people are sharing about the situation, but that's a disagreement about interpretation not facts.
Is there any evidence labels don't have option (3) provide some videos for free (presumably for promotional purposes) and pull the others? On what planet would Google forbid that? Practically speaking, how would they (absent the label cooperating for the takedowns by providing audio/video fingerprints, etc.)?
There might even be option (4) provide some videos for the paid service and pull the others, but that's more ambiguous because it's possible that could be forbidden contractually (e.g. if you participate in the paid services, you have to give it all videos you make public!y available or somesuch) and there are plausible reasons that Google might care.