I suspect that the VM gets suspended when you undock the phone. I wouldn't count on being able to use it for persistent background services.

This seems to suggest that at least the audio can't be relayed. Sad. https://www.samsung.com/hk_en/support/mobile-devices/how-can...

Texts are probably possible. (I use Pushbullet, but Android Messages would also work).

Only Apple seems to have got the control over the stack to get calls through iPad/macOS. I was hoping that Dell Connect would be an option but it's not clear that voice is pushed through there.

On Android, Termux lets you read and write texts using the Termux API, and set up an SSH server.

Termux:API[1] is close, but doesn't appear to support phone calls. You can record from the mic and send SMS though.

[1] - https://wiki.termux.com/wiki/Termux:API

"I was hoping this would allow me to ssh into my phone to make/take calls and send/receive texts. Does anyone knows if that's possible?"

I send SMS from the command line by curl'ing twilio ...

  curl -X POST -d "Body=Hi" -d "From=3032221111" -d "To=4151112222" "https://api.twilio.com/2010-04-01/Accounts/${account_sid}/Messages" -u "${account_sid}:${auth_token}"

I do at least half of my testing this way, from inside my terminal that I am already working in (I wrote a little sms script in /bin/sh).

Of course this means that your phone number has to be at twilio (either source the number from them or port it to them).

Kdeconnect comes to mind. It is more aimed at working on wifi, but you can probably make it work with ssh tunnels or vpn.