The profile that is visible on the website and which you set up, is only a part of what is on the system for higher status passengers. Personal preferences can be added by the purser, someone once reported that his preference for red wine being served in a decanter was on his profile. I guess pyjama size is similar to that.
I wonder if the purser can / would also record negative experiences with passengers (DYKWIA sort of behaviour for instance - not referring to a regular poster here )