Can someone with expertise explain what kinds of medical imaging are theoretically possible with this kind of sensor?

If you could obtain volumetric/3D ultrasound data that was not operator dependent, that would be great.

US is a good diagnostic tool, but it can be challenging to read because obtaining good images is very operator dependent. You need to have a good sonographer that can get the right views, knows how to adjust the imaging parameters to produce high quality images. It's not like CT or MR where the tech just sets a few basic scanning parameters and let the machine do its job.

However, see my other comment, the example images they provide on the page do not look great, very limited organ detail.

edit: clarification

More just interested in medical imaging in general but: unobstructed soft tissue imaging is possible with this, e.g. abdomen. You can get reasonably good differentiation between types of tissues using ultrasound in this context although there is the potential for ambiguous findings where further scans like MRI will be required to get less ambiguous information about it.

Chest cavity, brain tissue scanning etc. will likely remain unrealistic as ultrasound waves won't penetrate bone and the ribs and skull will interfere.