Didn't Vader gained height through the prosthetics?
hm.. seems that SW.com NOW claims he was (roughly) 6'1" as an adult.. used to say something a bit different.
In any case, this is an interesting read..
https://www.theforce.net/swtc/injuries.html
I used to have a link to one where it discussed the frame of his body not supporting the "shorter man with body extensions" claim.. can't find it now..
edit: actually it's on that same site lol
"Appendices
A. Vader in Health
Prior to the filming of Episode II there was enormous popular discussion about the representation of Anakin Skywalker as a healthy adult prior to his fall. The identification of potential actors was a matter of intense speculation, and the panic and excitement in some fan communities could be described as hysterical. The situation was exacerbated by provocative statements attributed to controversial (and short) contenders, and by the innately self-referential interaction between sensationalist media reporting and Internet-based fan rumours.
Therefore it is beneficial to review the objective evidence concerning Anakin's adult but uninjured condition.
Facts:
Anakin Skywalker had the torso of an exceptionally tall man. When he was penetrated by lightning in ROTJ we saw that his torso is essentially original and sized in proportion to his armour.
As Darth Vader he was riddled with prosthetics, but his body was in excellent proportion. His limbs were not out of scale with his head and torso.
When Anakin reappeared in spirit form in ROTJ he towered over Obi-Wan Kenobi. His spirit manifestation was free of cybernetics and presumably reflects the natural or potential condition that his body should have been in, as a man aged in his forties.
The ROTJ novel describes the pre-fall Anakin as "striking, and grand, with a wry tilt to his brow that hinted of invincibility and took in all life with a wink."
The representation of the adult Anakin Skywalker as a tall man is affirmed throughout many fields of licensed products: the action figure of his spirit form; the Japanese and English comic versions of TESB and ROTJ; his apparition in The Truce at Bakura novel.
In his late teen years, Anakin exceeded his master's height [Attack of the Clones] but was still growing [The Approaching Storm, p.20]:
Neither was physically imposing, though one had a build suggestive of considerable future development. .... [Bariss Offee found] herself facing an attractive young man who wore confidence like a handmade suit.
Conclusions:
Anakin Skywalker, as an unharmed adult and by his natural genetic potential, was destined to be an exceptionally tall man, over 2m tall.
He did not undergo any cosmetic [ad hoc] “limb extension.”
He needn't have been unusually muscular at any particular age. His apparent muscularity as Lord Vader might be the result of exercise and conditioning occurring after his downfall. "