Questions about it are good ice-breakers for shy visitors. Museums have a public responsibility to be as accurate as current scholarship allows. Since museums form public perception, they are obliged to do the best they can. As I said before, I think it is only desirable in certain circumstances. If the museum takes the matter on, it really should take it very seriously.
Costumes are for clowns.
It is insulting and insensitive to dress interpreters in costumes. It shows a disregard for people of the past. I am not suggesting the museums revert to ancestor worship, but I firmly believe that the most important gift that living history museums can give to the public is the spark of empathy in order that we might recognize people of the past as sophisticated, that we recognize them as fundamentally different from ourselves, and that we judge them on the terms of their culture, not ours. We have observed that visitors are much more knowledgeable about inaccurate clothing than they used to be. They may not know what is right, but many notice what is wrong, such as modern glasses, make up, jewelry, and the style of shoes.