If they paid a billion $ a week to be a nurse there would not be a shortage of nurses.

There would still be if it took years to get a nursing certification and essentially everyone with one was already employed. I can't just decide that I'm a nurse tomorrow and start on Monday, no matter what they pay.

Lots of people have left nursing in the past few years. If it paid a decent wage many would come back.

If you never fixed the criterial pipeline sure you would have a temporary shortage because that was your bottleneck. But there are plenty of people with equivalent skills, past or military experience that could do the job or be trained quickly to do it. It’s just a lack of desire to actually deal with the problem

You don't need to pay millions. But when you pay the minimum wage and exploit those people to the maximum, you get what you sowed. When they find a minimum wage job with better working conditions, they flee.

Hence why many fled for huge pay raises as travel nurses

In Italy IT salaries are going up, well above nurses ones, still there's not enough IT people. There simply isn't the people. Almost no one really grasp how bad is italian demography.

If you have to go through training and licensing, there would be, until such time as enough people have completed it.

Artificial barriers… real training barriers have some lag but can be overcome pretty quickly in a pinch.

Artificial or not (I argue not), my statement is still correct. I am not sure what you are defending here.