Yeah, the main advantage of giving your containers their own IP addresses is the ability to use Tailscale as a service discovery mesh. If you combine this with MagicDNS, this gets you most of an 80:20 of Istio with about 10% of the configuration required!
So if the local tailscale address is 1.2.3.4, I do:
ports:
- 1.2.3.4:8080:8080
This doesn't actually add applications to the tailnet as in the OP, but it works.