Netflix has barely tapped its global potential (partially more and more users of countries come online world-wide), and many companies have experienced what they call "demand pulled forward", i.e. extra growth in pandemic that then falls as pandemic heads towards a close. This is short term, and he has assumed that the slow in growth is the "inevitable decline" of Netflix Subscriber growth.
Also, to be clear, I think Stratechery is an incredible source and usually agree with him. I don't in this case.
I wasn't trying to respond to his points more directly, I was taking on the perspective of what is good for the companies growth.
Just because you "happily enjoy ad-free Netflix, YouTube and Hulu." Doesn't mean most do (and there are strong statistical reasons that indicate that others enjoy it more as well).