An MPH is very different from an MD or PA degree and it is a mistake to conflate the MPH with those programs. Despite the name, it usually isn't a degree that puts you into a direct "patient-care" healthcare setting.

Many graduates from the top MPH programs go onto leadership and management positions - for these programs, my experience is that there is a significant focus on the leadership aspect layered with specialist knowledge in policy, epidemiology, biostatistics, health care administration, etc. Many MPH programs will offer subspecialties like that - so you get, for example, an MPH in biostatistics or epi rather than a generic MPH without a focus.

Pay can vary greatly. Some MPH graduates will work in non-profits and others will wind-up running clinical trials at big pharma. You can imagine the kind of salary range those very different job types cover.

I would be extremely cautious about making a ROI judgement of the MPH. I know MPH grads who have worked as direct advisors to US senators, MPH grads who write biostats software, and MPH grads who help run rape crisis centers in underserved communities. There are also combined programs for MD/MPH linking up a school of medicine at a university with its MPH program. Those grads are often looking to lead research efforts or county-level health departments.

More generally speaking, I think you aren't wrong about NYU being an "excessive waste of money" but I don't think that has much to do with the degree in question. I have met too many successful people with "low ROI" degrees just in the software industry to feel confident about judging these programs in general. Which, of course, is very different than saying it is a good idea to rack up $157,000 in debt (like the student FTA) for any program from any school.