Hello,
I wrote a VNC viewer optimised for eInk screens and text workflows.
It achieves 30 fps.
Full screen updates break that framerate slightly, but no matter.
Please see the video and link below.
Read the entire document (github readme) before trying it out, please.
It mentions, among other things, that the only supported server is TightVNC.
Link to the repository (binary available):
https://github.com/everydayanchovies/eink-vnc
Demonstration video:
https://zmarshall.nl/static/einkvnc_demo_kobo.webm
Cheers,
Max