It looks like db is fried, I’d assume all the permission errors prevent it from running normally. Is there a healthcheck configured?

I would assume they want to factor in startup time as well as IO handling overhead - raw disk IO should be the same given programs are run in the same environment.

Popular choices include peertube and MediaGoblin

I wonder who knocked out over in the first place.

It’s recommended to install YunoHost on fresh, dedicated systems. It’ll most likely not break anything but it’s best to have backup ready. It is possible to then expose docker containers, but I’d just recommend installing Nextcloud in ynh and transfer the contents over.