I have no idea by what criteria, precisely, these videos or the PragerU videos were marked restricted. Neither does PragerU, for that matter; Google doesn't surface that level of detail on the Restricted algorithm to end-users. I've been making educated guesses at the detailed cause, but it's somewhat irrelevant; the answer is, really, "Google's algorithm deems this content should be restricted."
By that criteria, MSNBC and PragerU appear to be treated the same way.
(Edit: FWIW, I went ahead and clicked through one video and that micro-sample should probably be flagged for "politics;" pundit accusing the President of, at best, being ignorant of science, and at worst, misleading the American people intentionally. That's clearly inflammatory political content).
That's key to the current frustration with YouTube, outside of constitutional grounds: as a platform, it's become wildly unstable to depend on, as you simply are not given the ability to understand where it will or will not draw the line, and their application of their standards leaves such an ambiguous and inconsistent trail of evidence that it's harmful to everyone who tries to rely on it.
By that criteria, MSNBC and PragerU appear to be treated the same way.
(Edit: FWIW, I went ahead and clicked through one video and that micro-sample should probably be flagged for "politics;" pundit accusing the President of, at best, being ignorant of science, and at worst, misleading the American people intentionally. That's clearly inflammatory political content).