Maybe he thinks it will be stark and perhaps if he sees the subtle differences in white it will help. If the issue though is that he wants “color”, that’s different.
I loved the look of the warm white used in my living room so slowly repainted kitchen, hall and master. It’s so versatile when decorating and when wanting a change, easy to just update accessories (big advantage). In regards to the bathroom, I think it’s dependant on the counter, flooring and tile. Suggest trying to find inspiration pictures of white bedrooms and bathrooms that somewhat reflect what you are working with, to help with decision.
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Various shades of white with their undertones
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