I would say that a plain white t-shirt is preferable to the logo tees that a lot of people wear, with various offensive slogans and pictures on them.
Also, while I don’t actually have a white one, I have plain tees in a variety of colours - white is available - that definitely aren’t undershirts. Difficult to write rules that could differentiate between the two, though.
“I would say that a plain white t-shirt is preferable to the logo tees that a lot of people wear, with various offensive slogans and pictures on them.”
I would say that the plain white is as offensive as most of the slogans and pictures.