Because I've never measured their thickness with a pair of callipers, I don't know if Camry and ES roll bars are the same thickness.
However I do recall reading car magazines back in the 1980's and 1990's saying that the Toyota Windom (Lexus ES) was a lower roofline frame less winow version of the Camry, with sports heavy duty suspension including uprated springs, dampers and roll bars.

I suspect my 1999 Camry V6 have softer roll bars with more body roll.
I suspect the Camry dampers are softer with more comfortable low frequency vertical oscillations and float.
However, I believe the Camry spring rates are about the same as ES, because both cars tended to ride over the bump rater than flatten bumps out.
Thankfully the 65 series tires with baggy sidewalls absorbed most of the shock not taken by the springs.

Having said all that, the Camry suspension still handles quite well, while the original ES suspension was better handling, but thumpy and harsh.

Suspension design is always a compromize.


Back in the 1980's and 1990's, Toyota made sporty "hardtop" versions of their sedans that have slightly lowered rooflines with frameless windows, and heavy duty upgraded suspension.

1991-95 Corolla Sedan & Ceres Hardtop; the Ceres Hardtop was available in the Japanese Domestic Market JDM only.









1988-92 Camry Sedan, Camry Prominent Hardtop and Lexus ES250 Hardtop.
The Camry Prominent Hardtop was available in the Japanese Domestic Market JDM only.









1990-94 Camry Sedan and sporty Vista Hardtop - both in Japenese Domestic Market JDM Narrow Body Version.







1992-96 Camry Sedan, Toyota Windom Hardtop and Lexus ES300 - all in Wide Body versions.
The Toyota Windom Hardtop was available in JDM only.











1994-98 Camry Sedan and Vista Hardtop - in Japanese Domestic Market JDM Narrow Body version.











1996-01 Camry Sedan, Windom Hardtop and ES300 Hardtop - all in Wide Body Version.
The Toyota Windom Hardtop was available in JDM only.








The bottom line.
It's not just a co-incidence that Camry and ES use different suspension calibrations.
Different suspension calibrations can be used with different body styles.

By the early 2000's, TMC generally stopped building hardtops with frameless windows.
In other words, the Lexus ES would have framed windows too, however Camry/Avalon/ES continue to have different suspension calibrations, and that's a good thing because it gives us a choice to customize between a comfortable ride or handling.

The 2012-18 6th Generation Lexus ES had different suspension part numbers depending on whether it was the base model trim, or the Ultra Luxury Pack trim which was noticeably firmer and complained by many owners.

 

Some amazing models , this one especially.