A half dozen or so actors have said in interviews that the old days of being an actor were very tough because the people that were making the movies were said to "own the souls " in very very binding contracts.

I am talking about the 40's and 50's mostly , here.

I am wondering if there is any part of those strict and binding contracts on the actors , that made the movies better?

Does complete control over every aspect of a movie business turn out better movies?

I don't think it is a factor. There was dreck then and genius, same as now.

Now, perhaps, there is a little more flexibility because then, you might not be able to cast someone who was under contract with another studio. But, did that really matter much?

I doubt it. The studio system of signing someone to a five picture deal and then plugging them in because they had star power, vs being right for the role, certainly didn't help the film. Of course that still goes on today to some degree, but the actors are willing accomplices in the awfulness.