I have heard this multiple times, including in a documentary once. The claim is that the Master Stonemason, in historic times, did not have to bow to the King (generally implied to be from the British master Stonemason to the British King) 1, 2.
The Stonemason was the master of all craftsmen. And it is telling that the master stonemason did not have to bow to his monarch. - (Montey Don, Mastercrafts - E6 - Stonemasonry, 14th Minute)