I've resolved my curiosity now, and don't intend to try every Solus edition on a VM that is as constrained as that one. As one final experiment, though, I thought I'd try a GNOME edition, after which I'd feel confident telling my friend Nathan that he could choose any Solus edition for his kids' laptops. It was not as I expected, though.
GNOME installed on that same "constrained" VM, and my next step, as always, was to update it. It got so far as to download 455 of the available 640 upgrades, but then it locked up solid. I went outside for a while, and when I came back in, that VM was still locked up solid. I could only unstick it with a shutdown.
I only mentioned this now because the Solus web site says that 10GB of disk is enough for any of the editions. That may have been true back in the day, but with 640 upgrades to download and install, it's not enough today.
Incidentally my GNOME VM, which is pretty bare-bones, requires 12.56GB of the 32GB disk it's on. I'm not shocked that 10GB wasn't enough for it, but I thought perhaps that 10GB figure would allow a bit of leeway.
As I said at the beginning, I've now run out of curiosity regarding minimum requirements for Solus. I'm sure I'll soon find something else that strikes me as curious, and I want to try it, but until then ...