Hi Grace Marguerite Williams! How's it going?
You ask an interesting question about actors and actresses from different era. I see you have a picture of (Tyrone Power?) there. I am a big fan of film noir, myself.
I think the question is a little like comparing professional athletes and sports teams from different eras. Commentators are always ranking pro basketball players, for example, both as individual players and as teams.
People might say: Who is better, today's Golden State Warriors or Michael Jordan's Chicago Bulls of the 1990s, when they won those six NBA titles? On one level we think the answer is "obvious."
But one thing we must always keep in mind is that those teams, from different eras, played and play under different sets of rules. NBA basketball in the 1990s and 1980s was more physical because more physical play was allowed by the rules and the officials.
The other thing commentators say is that the Warriors are "changing the game," in the way they play "small," and all that. These commentators say that with the Warriors exquisite ball handling ability and general shooting ability (even three-point shooting), the opposition is actually forced to "go small," as it were to compete. If you leave too many "bigs" in there, the Warriors will just make them look clumsy and flat-footed with their superior speed, and all that.
Now, if we could transport these Warriors back in time to the era of Michael Jordan's Bulls' heyday, then the Bulls' size advantage combined with the more permissive, rougher rules, would probably go a long way to offset what the Warriors like to do.
Similarly, the actors of from the Golden Age of black-and-white films and today's actors functioned and function under different parameters and rules. In Tyrone Powers' day, it was the age of the so-called "studio system," which among other things, provided more ongoing "professional development" on an "in-house" basis.
Also, movies and actors of the black and white era were much more influenced by the theater. Before movies became their own thing, so to speak, they tended to more generally incorporate the techniques and visual style of stage plays, which everybody, then, was most familiar with.
If you really break it down, you would see that there are many, many differences between the way actors go about their work today, than how they went about it in the 1950s, say. Would Tom Cruise be as big a star in 1950 as he is today?
Hard to say without isolating the variables.