I see your example as a positive in favor of mastodon over other social networks.

When the one responsible for running the site can not run it anymore, it effects everyone on that website.

Examples:

- Digg (killed by owners removing their own product)

- Myspace (killed by new ownership leaving site to rot)

- Google+ (killed by Google)

- Facebook (killed by enshitification)

- Tumblr (killed by new ownership's rules)

- Twitter (killed by unhinged new ownership)

But mastodon is actually decentralised by design and implementation.

Mastodon as a whole isn't a single website, but instead is a whole collection of groups each running on their own server that can interact with each other as if they were one large site.

So with mastodon: when a site runner loses their ability to keep a site running (e.g. your example), only the single mastodon server/group is affected, the users move to a different group, and the rest of mastodon keeps running as if nothing has changed (because in the grand scheme of things, nothing has).