I feel like there is a huge difference between a shared kitchen and a shared bathroom. I'm fine with the former, and I would personally take that if the price was right.
But the latter is gross.
But the latter is gross.
I feel like a toilet, shower, and sink could be added to an efficiency apartment for 3m².
If people want to see how small a room could get, see ships, especially crew quarters. I could probably design something with a kitchen, bathroom, washer and dryer, bed, desk, and storage for 15m².