Nowadays it would be more practical to add ESP32 support to uClinux and skip the unnecessary performance hit of the VM.
No kidding! My intro to X was seeing it load bare-bones on my enthusiast friend's 2M (could have been 4) 386.
I think he brought xfontsel up or something and you could see the scanlines being drawn one at a time :)
A couple of years later, I was running fvwm2 and a very serviceable desktop at work in 8M though. (AFAIR, anyhow.)
With the wireframe mode, it's even faster on moving and resizing.
Implementing a wireframe mode on CWM should be dumb easy and a lot of older machines would profit from that.
But back in the day you could browse without images perfectly fine, as the important ones where under galleries with custom links and downloading them was really slow.
This was my setup for a considerable amount of time. Even though it is hard to believe in our fast paced times it must have been for several years.
The 386DX with 4 MiB was my first Linux machine and my first PC for that matter. 4 MiB was not enough to even run the Slackware installer, so you had to partition and mkswap manually from the command line before you could run it.
Apart from that it was a pretty workable machine for those days standards. I used it from the console most of the time, but X11 worked, even if it was slow as molasses, as you said. I remember running GNU chess. While you could play from the command line it was one of the apps where the GUI was really helpful.
Good times!
Also, when writing, it's probably better not to have a multitasking OS - no distractions ;-)