Definitely working for my little one! He started getting a bald spot and I used to find a bunch of hair every morning on his sheets but now there’s no hair coming out and he has baby hair growing. I bought satin pillow cases though and not silk sheets as those are so expensive. The ones I got were 2 for ~£7 on Amazon.
I definitely notice the difference between silk and cotton and even one night on a cotton sheet and her hair looks a right state!!! All I did was buy some silk pillowcases from Amazon though and cut them up to make smaller strips to attach to the sheets. Bit of diy craft instead of £50 per sheet