ClearOS Community basically died. They still exist but only to continue support for existing customers. It’s not active and it hasn’t really changed since 2013.

Basically, everything ClearOS does, another product does better and free-er. TrueNAS Scale for storage, Proxmox or XCP-NG for Virtualization, and both TrueNAS Scale and PVE have containerization support, so you can spin up the services you actually need using a technology that’s modern. For the full package, Univention basically took the ClearOS approach and made it on Ubuntu. In the network side, VyOS and PF/OpnSense took over routing, while the Sense products plus PiHole and AdGuard Home made DNS management easy.

You don’t even need to register the domain through Cloudflare, you can just set up Cloudflare as the DNS master, and they’ll put in the right DNS records when you configure Email forwarding.