I will try to get you a clean snap list and snap changes tomorrow on a freshly-deployed image, but it’s worth noting that I only installed the docker snap here manually:
Name Version Rev Tracking Publisher Notes
amazon-ssm-agent 2.3.978.0 2012 latest/stable/… aws✓ classic
core 16-2.45.1 9436 latest/stable canonical✓ core
core18 20200427 1754 latest/stable canonical✓ base
docker 19.03.11 471 latest/stable canonical✓ -
lxd 4.2 15753 latest/stable/… canonical✓ -
And yes, looking a bit closer, you are right and my issue might be a bit different to OP’s and sounds more like the one @popey was facing in this thread. If I wait a while (or add a reboot before the snap install stage) I am able to install Snaps.