If so, that means the ship cannot visit any port, harbor or waterway which requires a locally qualified marine pilot onboard.

It also likely affects international treaties regarding the obligations of the master or officer in charge.

If the computers go down, and with no one aboard, is it considered abandoned? Can anyone claim salvage rights by hooking up a tow?

Currently, "vessels have an international duty to give reasonable assistance to other ships in distress for saving lives" (quoting https://en.wikipedia.org/wiki/Marine_salvage). How does that duty extend to uncrewed vessels?

I'm sure there are lawyers salivating at the chance to resolve these questions.