rms and the GPL focus on distribution, yet the Internet has enabled large firms to gain control without distributing their software, or even while distributing FOSS software. Perhaps tomorrow Google open-sources the JS executed by google.com in their open source browser, and it makes no difference, because the important bits - what data they retain about users - are not distributed.
Software we never run on our devices may yet control us.
AGPL tries to solve some of these problems, but fundamentally any service which controls and operates on your data on a server you don't own cannot fundamentally be free. RMS calls such services SaaSS (Service as a Software Substitute).
So while distributed systems under AGPL still protect your freedom, AGPL of a SaaSS (like Google Docs) are non-free because you cannot change the software running on the server (and of course you shouldn't be able to -- because that would violate the freedom of the administrator). SaaSS is fundamentally incompatible with software freedom.
(And this is something that RMS has made clear arguments about. He cares more than just about distribution.)
Software we never run on our devices may yet control us.