I have a more cynical take; the recommendations declined when Netflix started producing their own content. Prior to this, what constituted a "good recommendation" was aligned between Netflix and the customer, but afterwards not so much.

Today Netflix is in the "how do we get our customers to use our service as little as possible but still pay us every month" phase of their mediacom hypocracy. From a business standpoint, that is their best optimization. They are AOL/TW from 20 years ago.