From the original article:

The Tor Project has explained its recent decision to remove multiple network relays that represented a threat to the safety and security of all Tor network users.

…Tor Project discovered that some relay operators engaged in a high-risk, for-profit cryptocurrency scheme that promised monetary gains with cryptocurrency tokens without endorsement or approval of The Tor Project.

If the “for-profit” element is to take scale and consume a large percentage of the Tor network’s relays, power from the community would fall into dubious hands, and the network’s safety would be undermined by invasive centralization.