What do you think Cloudflare’s core business is? Because I think it’s two things:

1. DDoS protection

2. Plug n’ Play DNS and TLS (termination)

Neither of those make sense for self-hosted.

Edit: If it’s unclear, #2 doesn’t make sense because if you self-host, it’s no longer plug n’ play. The existing alternatives already serve that case equally well (even better!).