I am disincentivized to run my own instance, aka "distribute". It pushes for centralization. On multiple fronts. Why? Well for starters the protocol as i'm aware of does not efficiently federate to smaller instances compared to bigger instances.
I also fear that instances will eventually be plagued by spam / attacks from foreign small instances and will be pushed towards whitelisting federation rather than blacklisting. As the general philosophy of federation seems to match that of Email. Email.. tbh, feels like a failed technology. Yes i know, i love email and we all use it.. but it's incredibly centralized and insanely vulnerable to massive amounts of spam. The protocol almost pushes people to centralize to deal with problems that the Email protocol doesn't manage - spam. I fear Mastodon will eventually follow the same path.
I use it, but i have to ignore the protocol and my desire to decentralize.. because otherwise i just get frustrated.