That doesn't require unpredictability. For example, Mersenne Twister seeded from /dev/urandom would work fine for that, even though it's predictable because Mersenne Twister is predictable.
I see you’ve replied to quite a few of the comments in this thread, but I think the basis of the disagreement isn’t in the specifics, but because you’re using a stronger definition of “unpredictability” than they are.
Today I learned that there are other aspects for CSPRNG beside the stronger definition of unpredictability. Wikipedia mentions inability to calculate previous values in case the hidden internal state gets revealed. So I assumed that top question was intentionally asking about weaker definition of predicatability not PRNG that have good enough unpredictability for CSPRNG but doesn't match other requirements.
I believe I'm using the same definition of unpredictability as the website. If other people are using other definitions that is indeed going to cause a lot of confusion.