My theory is that there is quite a few servers that are chosing to defederate. The number of total servers continues to drop according to fedidb.
Or admins are just finding it not worth bothering with administering their own server and turning them off.
Exactly. To extend the junk food analogy, this is like making donuts from scratch in your own kitchen: customized to your preferences, maybe tastes better, but ultimately you’re still making a mess in your kitchen and eating unhealthy.