Come On Giant Asteroid!"have all-powerful leaders" ... OK, well, in some sense yes. What they have is owners & no matter how benevolent when the platform starts, eventually the Money People arrive & then everything becomes about "shareholder value". If extracting every last quantum of value from the company kills it ... well "free market" & off they go to do the same at the next place.
AFAIK (and may be wrong!) there is no prohibition against for-profit Mastodon instances. Same could happen at one.
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