Algorithms other than FIFO are fine when they serve you. Way back when I had a mail reader (Gnus) that used a Bayesian classifier to predict which emails I might especially want to read, based on past reading experiences. That was nifty! An RSS reader could do the same, on my own machine, based on my own preferences and not some marketer’s. I’d like that an awful lot.
You sort of can with very little work. When I used RSS more I had a "primary" folder and a number of secondary folders. I always looked at the primary; I'd dip into various secondaries when I had the time.
I do sort of agree with the general premise. The sort of social media that sort of replaced RSS is largely dead.