You can. I did. Follows are a kind 03 event and I just copied that e tags into a kind 3000 list event. Anyone can now use my list, by cloning it into their own kind 3000 event on listr.lol. They could use that for onboarding or starting up a new relay.

Next step is to auto-update a relay based upon changes to the list, and delegating curation of the list to a group of relay moderators. Might be coming to relay.tools from nostr:npub10npj3gydmv40m70ehemmal6vsdyfl7tewgvz043g54p0x23y0s8qzztl5h eventually.