Wouldn't Tsitsipas's high backhand RPM be due to him hitting one-handed? Same with Thiem.
Saw this set of data from the same author (
https://pbs.twimg.com/media/FSRKUTtWQAUfmsE?format=jpg&name=4096x4096). The highest backhand RPM's are from one-handers with the exception of Ruud. I don't find this surprising as 1HBH's can brush over the ball more. I find that forehand RPM is a better comparison as all of the top 100 use one-handers. These are the "heavy topspin" FH players according to the graph I linked.:
- Delbonis 16x19
- Ruud 16x19
- Berretini 16x19
- Duckworth 16x19
- Nadal 16x19
- Jack Draper 16x19
- FAA 16x20
- Alcaraz in 2021 16x20
- Musetti 16x19
- Djere 18x20
- Jordan Thompson 16x19
- Kecmanovic 16x19
- Alcaraz in 2022 16x20
- Steve Johnson 16x19
- Tsitsipas 18x20
- Basilashvili 18x20
- Fognini 16x19
These are the "flat" FH hitter section:
- Mannarino 16x19
- Gilles Simon 18x20
- Medvedev 18x19
- De Minaur 16x19 (I think?)
- Giron 16x20
- Andy Murray 16x19
- Moutet 16x19
- Evans 18x20
- Hurkacz 16x19
- RBA 16x19
I wouldn't be surprised if I'm missing anyone or got any of the string patterns wrong but of the top 17 "heavy topspin" FH, there were 11 with 16x19, 3 with 16x20 (2 of them were Alcaraz for some reason), and 3 with 18x20. Of the 10 "flat" FH, 6 were 16x19, 2 were 18x20, 1 was 18x19, and 1 was 16x20. I'm really not going to spend the time to look at those in the middle. So about 65% of heavy topspin FH were from 16x19 and 60% of flat FH were from 16x19. All this really tells me is that 16x19 is more popular overall. More 16x19's means that it's more likely that a heavy topspin player will be using one. My non-scientific explanation for this is that 16x19's are generally easier to play with so more people learn with one and just stick with it.
As far as spin generation, I'm not convinced that a 18x20 player like Tsitsipas would automatically increase RPM's by swapping to the 16x19 version of his Blade/H22. Pros pretty much hit exclusively in the sweet spot where the difference in string density between 16x19 and 18x20 is not that extreme. I think most players mistake the springiness and higher launch angle of a 16x19 as increased spin, however if you're not imparting the ball with RPM's then it's just a flat ball that's clearing the net more..