Merlin Mann, back in 2009 or so, on Marco Arment. The piece itself is showing its age, but this part caught my eye:
I’m still mulling over the longer term consequences of a post-RSS, post-API culture that destroys any reasonable barrier to putting all the data that matters to you any place you want any time it suits you.
Alas, the opposite of that happened instead.
Also, gosh, 2009 was 10 years ago. Merlin was cranking out quite a bit of writing back in those days.