Pretty much everything here was obvious to me years ago. In the sea of trolls, astroturf, feds and mentally ill people online, political organization is not really possible. The state has 0 problem with this, as it allows the machine to trundle on unobstructed.

Once everything becomes a game of posture and affect, will it ever be possible to articulate a coherent politics again?

It's been this way for a long, long time. The only coherent politics remains anarchism, because it's the only option. You live in it now, get over it. Being honest about it makes things better, not worse.