Hi Ken,
Yahoo groups seem pretty dated and clunky but certainly served a need.
From a google browse, you can clone or archive the Spectroscopy groups so they aren't lost forever but getting that data to another (non groups.io) site doesn't seem to be easy.
As for alternatives, have a look at Hostinger or Proboards (free) on
https://hosting.review/web-hosting/b...forum-hosting/
Many people who game will already have Discord, which is nice and easy to use and set up.
Just a few thoughts Ken.
Stu