Tom, I think you are old enough to remember that in talking about the best players of 30+ years ago, we would often refer to who had the best stroke. That is rarely even mentioned today. The equipment in use today, has in some ways made the game easier. No longer is a powerful stroke a necessary attribute to being a top player. Pool remains the same game, with 9-Ball and One Pocket still the most popular versions, just as they were 30 and 40 years ago. But the way the game is played has changed dramatically, for the reasons you stated above.
My own personal opinion is that the best players of yesterday are the equals of the best players of today. I saw great players in the 60's and 70's, a lot of them. The difference today imo is that there are more good players, because of the way the sport has expanded. It used to be a national sport, primarily confined to the USA. No more. Now there are good players everywhere!
I will add this though. I think the best rotation players today at games like 9-Ball and Ten Ball may be playing at a higher level than ever before. I seriously doubt that I've ever seen better pool shot than by young Mr. Wu or his compatriot Yang. Same could be said for the top filipinos, although Dennis looks to me like a young Parica clone, with a very similar style. I would put Parica in the older generation and perhaps Efren as well, and there aren't any current players (other than the two I mentioned) that play any better than these guys.
I still say Ronnie played One Pocket at a higher level than just about anyone I see playing the game today. Ronnie likes to tout the top young players, that's just always been part of his hustle. It comes naturally to him to tell everyone how good they play, just before he beats them. He did that same thing for years. He would tell a guy he plays way too strong for Ronnie to spot him a ball and Ronnie would give him three balls anyway, and "outrun the nuts" as he liked to say. There is not one player today (other than Efren) that can play the way Ronnie did. Of course, Jersey Red, Eddie Taylor and Ed Kelly were not far behind either. Those later three in their prime would give any and all of today's One Pocket heros fits. Yes, Scott Frost has a big game and Gabe is a very clever player, but if you think that they would be the favorites over the best old timers I would have to disagree. Even the best of my generation, Mizerak and Sigel, played exceptional One Pocket even by today's standards. Same for Buddy.
Again this is just my opinion based on what I see and observe. Bottom line, the best players of yesterday were just as good as the best today. There were just fewer of them then. If you could somehow bring Harold Worst back, he would still be a winner. He had talent, heart and character! In large doses I might add. He was the kind of man who would figure out the equipment and how to play within days. He was the "Efren" of his era. And once he got the hang of the game, you were dead! He had more heart in his little finger than any ten players I see today. Parica also had a huge heart. Don't get me wrong, there are players today who exhibit a lot of courage and heart. But none are any better than Harold, Parica or Cornbread. These guys were fearless and embraced all challenges. I never saw any one of them back down from anybody!