no
actually arnolds arms measured at 19 3/4 according to aurthor and sergio said in a interview some years later that the measurements were accurate at the time(his measured at 20.5).
the magazines claimed his arms were 22 inches and he said they were never that big, and sergio had bigger arms than arnold.
Lets not forget how much bigger an inch on your arms and lower bodyfat can make you arms look. Mine are just about 19 inches now, that 3/4 of an inch and 3% bodyfat difference arnold probaly had on me would make his arms look not 3/4 of an inch bigger but maybe 2.
That was probally done when they were in peak condition 6-7% bodyfat. Compare that to the pros of today with 22 inch arms at 4% and you can see how the standards have changed.