Starlink uses CG-NAT (a way to provide IPv4 addresses that are not actually real IPv4 addresses) and does not work with the current implementation of ARC:
There is now an update in earlyrelease testing that shall make work ARC with the new IPv6 and hence hopefully with all CG-NAT afflicted ISPs.
If you want to (but I don’t know how comfortable you feel about that as a new user; though it’s not actually challenging and as you have experience with a little network troubleshooting you will be just fine) you can join earlyrelease testing. It may be valuable for Roon to have testers with Starlink. Else, a bit of patience and hopefully this version will be released soon to all users. The instructions for joining earlyrelease testing are here:
The info about the IPv6 testing is here in the #early-access area of the forum: