It states: "The term "distribution" here means the ability of picking one or more resources on a certain Sling instance in order to copy and persist them onto another Sling instance. "
If you wanted to sync other types of content, then you would have to extend SCD and implement it yourself.
For UGC Adobe moved away from trying to replicate content(i.e. copy) across instances, instead a common store approach is now recommended, which is implemented in Communities. (SRP - Community Content Storage ). If you are not using communities then I suggest to consider implementing the same pattern.
