There are several specializations in sonography. Besides OB/GYN other fields include cardiac and vascular.
The sonographer isn’t really responsible for patient care, i.e. getting them in and out of the exam room and dealing with issues unrelated to the scan.
BTW the Sonographer should not give any indication of what the scan shows, your doctor should be the one doing that. There is probably some slack for pre-natal about the obvious yes/no & where is it.
Sonographers do see some remarkable things, amazing and alarming, all of which are supposed to be communicated to the doctor for expert analysis not to the patient.
Depending on the region sonographers can be more underpaid than you would imagine. In some regions there is a glut of sonographers and most employers take big advantage of them. In some parts of the country they are still paid reasonably well, but nothing like the PAs and MDs.