Technique can change by kind or by degree - at the pro level most are by degrees; it’s very hard to change the overall style of your shot this late.

Djokovic’s forehand was essentially the same kind, only shortened (still was a great change).

The same can be said for Thiem’s adjustments in 2019 where he shortened his forehand in particular to be able to play up in the court and beat the big-3 consistently on hardcourts.

Djokovic’s serve is another case: it was great in 08, then 09/10 he developed a kink, then got it back in 11, but improved it with the scorpion lag later in his career.

Wawrinka’s technique was always very similar in my eyes, but I’ll go back and watch some 2010 stuff of his because I do that in my spare time anyway.

Nadal’s forehand had many iterations, some better than others. His grip was a little more extreme in the earlier days 07-ish, but the worst in my eyes was 2009 and the best was 2010/2013 style.

Ruud adjusted his backhand midway through 2022 and had good results in the second half of the year with a fuller takeback.

Agassi shortened his groundies late in his career to also enable him to maintain a hyper aggressive court position.

Alcaraz has shortened his backhand since his 2018/2019 junior days to play more aggressively.

The list goes on. The single best change I have seen?

Thiem for me.