The next couple of years will be slightly more interesting that usual to see if regulation plays out for ON and AB, yes, and how that will impact the PA profession. This is a topic I've been reading about for some time so I will summarize some thoughts below.
It's very difficult to compare the timeline of regulation/legislation of PAs in the USA versus Canada. The easiest comparison is at the national level: it took almost 30 years (from mid 1960s to early 1990s) before American PAs were recognized by the American Medication Association. If we take the same starting point of "first PA education program", then Canadians are just over 10 years into PA development nationally and we are obviously not at the level of well-established national recognition. If we look at it state by state and by province/territory, it gets more complicated. It's clear the idea of PAs was picked up much quicker in the USA but the development was still gradual. For example, the first legislation/regulation for PAs was in Colorado but only for "child health associates" in 1969. PAs did not start prescribing until 20 years later (1980s). A uniform rate payment for American PAs was not established until 1997. I can't find any data that would allow for comparison of PA employment rates of American PAs in the 60s-90s compared to Canadian PAs now (would need to take into consideration population and economical differences and I am not sure this comparison is even possible). Sources: https://www.aapa.org/wp-content/uploads/2017/01/History_Milestones.pdf; https://capa-acam.ca/wp-content/uploads/2018/01/JAAPA-50-Years-PA-History-ebook.pdf
As for job prospects of PAs compared to doctors, nurses and NPs. I have not seen any reviews that allows for comparison so if anyone has some information and insight on this, feel free to share. I just know that there are common themes when you hear about the issues raised among nursing unions and medical associations. I suspect that PAs are probably more impacted by the same issues given our lower numbers (and thus representation in financial budgeting) and in-development infrastructure. I get the sense that if you are willing to relocate, compromise on hours and pay, be flexible with your field of practice, then you will find a job as a nurse, NP or doctor no matter what. This may not always be true for PAs given provincial restrictions to practice and lack of pre-existing infrastructure in some cities/hospitals even though PAs are practicing in the province. But if we are talking about people finding a full time position with good pay and hours in their field of choice, I'm seeing the same problems in all health care professions.