Yes, you have hit the target.
I try to give an example on my game.
When I played in the 70s and 80s I approached often and 8 times out of 10 I won the point. On the other hand, the weak shots were the winners (ace, baseline winners and passing shots).
Now that I am older than 30 years and I play worse I make many more winners but I have become very bad in the approach and I make 3 or 4 points out of 10.
I like the same to try but the result is bad and I get tired a lot more because the approach is much more difficult than to stay in the baseline.
My opponents have twice the power of 30 years ago and the passing shots annihilate me.
In the past an approach shot down the line with slice and depth worked very well but nowadays you have to force the opponent to be rushed perhaps to barely be able to return the approach in order to volley safely. It's the racquets and strings with the greater spin and power.
I'm not as effective at the net as I used to be but to be honest I think it's because I lost a few steps more than the racquet and string tech. I never used to miss an overhead but nowadays I can't move into position as well. I guess it's karma in a way since I used to wonder why people had trouble with overheads. I thought it was so simple to jump and smash it. Not so simple now.
I think the Connors' type approach shots would still work well because they were often so forceful that unless you had a great passing shot he would generally have an easy volley. However Laver, with his floating approach shot as Arthur Ashe put it would be eaten up. Ashe thought peak Borg would have passed Laver easily with those approach shots. However I do think Laver would have taken a different approach (pun intended) to approach shots today. I could see Laver driving a ball into the open court if not for an outright winner, at least a set up for an easy volley. Laver also had a heavy slice that was low, penetrating and deep that I think would still be effective today. I saw Sampras hurt Agassi with some of those approaches at the US Open in one of their matches.
I guess in that way you could argue the Pancho Segura forehand or the Federer type forehand approach were the best approaches since often they were for outright winners.
I felt Borg had excellent approach shots on grass but it was often different depending on his game plan. I saw Borg approaching against Connors at the 1978 Wimbledon purposely shot to the uneven patches on the forehand side in order to force errors or force Connors to hit up.
Fred Perry's forehand approach was often on the half volley which obviously was on the rise so the opponent would have less reaction time and Perry, who was extremely fast and quick could volley the ball away.
Edberg had a very good approach but I felt it was vulnerable to great passers like Agassi and Connors but then again, I guess everyone would have some problems with Agassi's and Connors' passing shots.
If we include a powerful serve into the mix as sort of an approach shot, I would say Kramer was probably the best of all time. His serve was arguably as great as any, combined with his excellent slice, topspin or sidespin approaches. Kramer's sidespin forehand approach was known for pulling his opponent off the court leaving Kramer a simple volley winner.