There may be a mobile base unit at some point in the future, but it will be comparable to the current Fleetbroadband units and therefore too power hungry and too big for your average cruising sailboat. Essentially you need a motorized dish which tracks and counteracts boat movements the entire time it's active. That's what is inside those Inmarsat domes you can sometimes see on big racing boats with satellite uplinks like the Volvo Ocean Race.
Not at all true with Starlink, it uses a phased array antenna to aim the beam at the satellite; everything happens in software. What _is_ needed is an accelerometer which can "know" the boat's movement and then adjust its aim based on that. Seems like they're not quite there yet, but there's no reason this can't work.
People have ideas about remote work on board, but for various reasons this rarely works out in practice. Internet connectivity is poor and intermittent, your schedule is ruled by the weather and having to work seriously distracts from the fulltime job that cruising is by itself.