I was at the Stedelijk Museum in Amsterdam back in August. Modern art, well organized. Their main collection is organized roughly chronologically, which I really appreciated. It helped put things in context, which is often a problem at modern art museums. It had fairly good signage, too, to help you navigate.
The bathroom, however, was a problem. It has virtually no affordances. I went to the one at the bottom of the newer part of the museum.
Very modernist. Each stall is a floor-to-ceiling white door, with a definite lack of signal to tell us if it’s occupied or not. Then, you get to the sinks and mirrors. A big mirror above all of the sinks, with hand towels hidden behind the mirror. You have to look under the mirror to figure out where they are, then reach across the whole sink and pull them out from under the mirror. Very complicated.
I suspect this is a problem for most modern art museums in new buildings, as the building are frequently designed to be statement pieces, including the bathrooms. I definitely had similar feelings about the bathroom at Centre Pompidou.