This is in part due to Mastodon's weird style of federation which almost comes off as a second thought compared to using it as a centralized service, since to federate with others you have to either know who to follow already or need to use a relay.
This, I feel is especially notable for Western nodes since they don't really seem to bother with relays (which I think largely defeats the point of federation by creating incentives to stick to large nodes). A lot of the relay lists are either super sanitized/focused on uninteresting topics or are dead.
In comparison, in the Japanese community there are several fairly active open relays (with some moderation to prevent abuse) and thus it's pretty easy to setup a custom node and have it populated with some basic content to build off of. As a result of which, ~75% of the traffic to my node comes from Japan, ~20% from the US and ~5% from Europe.
This, I feel is especially notable for Western nodes since they don't really seem to bother with relays (which I think largely defeats the point of federation by creating incentives to stick to large nodes). A lot of the relay lists are either super sanitized/focused on uninteresting topics or are dead.
In comparison, in the Japanese community there are several fairly active open relays (with some moderation to prevent abuse) and thus it's pretty easy to setup a custom node and have it populated with some basic content to build off of. As a result of which, ~75% of the traffic to my node comes from Japan, ~20% from the US and ~5% from Europe.