Guest Bathroom Happiness

Is it just me or is it impossible to get guest bathroom happiness above 75-80% regardless of museum size? I've done everything I can think of to make it better: gold everything, max deco, music, gender separation (not convinced that even works), bathrooms all over the place....nothing moves the needle. If I hire more janitors and only give them the cleaning assignment that doesn't seem to work either, possibly due to having almost as many cafeterias as bathrooms.

If anyone has a tip on getting this stat above 90%, please share with the class!