Part of what makes any role play/costume type fetish work is that there is something rare or unattainable about the situation. It cane be something that is every day common or banal. There has to be a hint of the forbidden, of breaking the rules of of normal life.
Obviously a maid is a domestic servant, something that most people won't encounter in their lives. To have a domestic servant, much less one in "uniform" implies a degree of wealth, a socio economic situation that most will never reach. Take this a step further in that most of the women who would work as a maid generally aren't going to be pretty since an attractive woman, especially one of a lower social class likely to take work as a domestic, has other prospects. Now take it further and make her uniform "sexy" and you have a very rare situation indeed!
For a man this means a fantasy of wealth and power. Not only is the man rich enough to have a servant but also fortunate enough to have an attractive one who dresses in a way to arouse. Since that sort of situation probably also implies a family, the man is powerful enough to abuse the situation and force the domestic to satisfy his sexual desires.
You could take pretty much any other uniform fetish and break down how it subverts a usual situation as well even those where the uniform implies that the woman is in an official role. Woman dressed as a police officer? That is certainly a subversion of the normal rules of encounter. Same for woman dressed as a nurse/doctor, etc.
So how does Japan ruin these things? Basically by making it over common to the point of banality and in the process of commercialisation, lowering the quality standards to the point of meaninglessness. That is how you get from
to
Take something nice, commodify it, grind it down to the bare minimum and price it so cheap that any Shinichro off the street can afford it.
No more fetish quality than something I can get from the combini.
