Using it increases the adoption numbers which can lead to more adoption, and therefore funding. It's indirect, but it still shows support for the author.
To me, DHH being a toolshed isn't even the worst part of an LLM coded slop "distro" that recently had a significant RCE vulnerability that required the bare minimum to exploit. Every OS / distro also has vulnerabilities pop up, but that's a known issue with slop code. DHH being a racist cunt is just the cherry on top.