You specifically stated that 50 million immigrants entered the US in 2019. That is incorrect. The amount of total immigrants in the US was 50 million. Understand the difference?
I think you know this but many if not most migrants are interested in not taking temporary residence in the United States.
That is the heart of the immigration problem.
So frankly, yes I think this distinction as one might try to apply that the United States is meaningless. It is unfortunate but yes meaningless.