Pacemakers will not slow down the heart rate—just speed it up and steady it. So it probably would not help POTS patients. Though I did have tachycardia sometimes and it stopped after I got a pacemaker, I don’t know why that would be. Perhaps because my pacemaker will outpace PACs which can lead to various arrhythmias and tachycardia.
POTS is definitely not normal! I see an electrophysiologist and she is familiar with dysautonomia and POTS but not all electrophysiologists would be. Ideally you would look for an autonomic specialist but they are very rare. You could phone local electrophysiologists and ask if they would treat the heart manifestations of autonomic dysfunction. I hope you find someone!