"What is up with this? I followed somebody but their toots are not showing up in my timeline!"
Maybe you *requested* to follow them. In the #fediverse people can choose to approve their followers, and your request might not have been approved, may even have been rejected.
It is a different world view here on #Mastodon compared with the bird site. How many followers is not a good metric here.
One of the more interesting things I have been noticing lately is #insularity.
As a site grows in number of active users, they tend to interact *more* with other users who are not on the same instance. The largest instances with real people consistently drop to a bit below 30%.
My working assumption (without specific evidence) is #social people explore by conversation, exposing themselves to new ideas, people.
There are, of course, exceptions.
If you take a look at https://www.fediverse.space/ you will see a visualization of #mastodon and #pleroma instances which are public, and some analysis of the public feeds of these instances.
If you take a look at https://www.fediverse.space/instance/mastodon.uno you will see a visualization of Mastodon.uno, an instance which is reasonably large but in a language group which as yet does not have many instances - and its details tab says it is 90% insular - most tweets are within that instance.
1/2
It might be the case that insularity also describes the internal health or connectivity of an instance. One I ran across had an insularity of 6%; almost no one is actually talking to each other on the instance - nearly 1k authors saying many things, but shouting into the internet and not developing conversations.
At the other end of the spectrum are a few sites running intensive bot communities. Gab and allies are ~96% and newsbots.eu, bots.h.kher.nl are both 100%.
3/3
@wsaewyc I guess when joining Mastodon people want to meet a smaller group of people. When an instance gets too big, they start finding friends elsewhere?
I think similar problem happens when IRC channels grow, then they just start requiring nick registration for people to join and this limits the growth somewhat. Artificially. I don't like it. I like to think that it would make sense to solve this by splitting the large group into two-three smaller ones by topic.
@gry
In contrast, https://www.fediverse.space/instance/mamot.fr Mamot.fr, a largish instance, has a 26% insularity ratio - #toots there are mostly mention accounts outside the instance.
That is actually lower than some of the most-active large instances. Mastodon.social, arguably the largest population of real humans, is running 33%. Fosstodon.org is 27%, Anarchism.space a frighteningly low 20%, Social.coop back at 33%.
2/3 (cuz I just thought of an interesting idea)