I often hang pictures in bathrooms. If they are original Van Goghs, probably not, but if they are framed pictures that do not have high sentimental or financial value. Go ahead. The worst can happen is that they wrinkle over time (which will be an indicator you do have a humidity problem).

I always hang art in the bathroom. This is my half bath with a framed print under a sheet of acrylic. A second print faces the toilet.

In my master bath I have both prints and a 3' X 3' unframed canvas. All have done well for many years.

I have seen friend's homes with great pictures hanging in the bathroom. Go for it. Then post some photos for us to see how it looks!