I ended up pulling the DCM fuse, but it comes at the cost of no microphone for phone calls and voice commands and no front speakers (and obviously no STARLINK).
I did the same after having a shop investigate the drain. They didn't put all of the pieces together as the OP did, but they pointed to the fuse and told me I could pull it.
You can probably easily rewire DCM from always-on to ignition-on. No battery drain and working equipment.
Yep, you just need to move the fuse to a portion that's wired through a relay. Some engine bay fuse boxes have spare relay and fuse positions to add these kinds of things; otherwise you can buy a small automotive fusebox and a relay and a couple dollars in cable and crimp connectors and then you just need to find somewhere to mount it, likely above the outside of the glovebox or such.