besides just getting backups going of all the previous data troves that the subreddit have enumerated, I was wondering what the best resources are for databases of all local governments. currently, I've found these: https://www.kaggle.com/datasets/max-mind/world-cities-database https://www.census.gov/data/datasets/2020/econ/local/public-use-datasets.html
imho, there could be a much more unified global dataset of all publicly available IRL communities, feel free to sanity check this.
There's also this site to browse communities
Home of the sh.itjust.works instance.
There's also this site to browse communities