Yes, it should.
Using a VPN would be another option. Also check out the FAQ entry regarding this topic https://gitea.wildfiregames.com/0ad/0ad/wiki/FAQ#what-shall-i-do-when-joining-multiplayer-matches-fails-with-an-error-message
In that case you just require a public IP address from somebody else (Cloudflare in your example). Some kind of public endpoint at which a host is available at will always be necessary. In future we might improve the situation by also supporting IPv6, but that brings its own set of challenges. See https://gitea.wildfiregames.com/0ad/0ad/issues/4301 for details.
You can join games where servers are hosted on public IPs without NAT being involved. That's true for Minecraft, Wuthering Waves, as well as 0ad hosts who do proper port forwarding.