I went through a phase of using ~whitenoise while working to block out distractions.
Actual white noise indeed sounds really bad and grating. The best for me was a mix of pink and brown noise, pink for an ~equal baseline and brown to make it sound a little more mellow.
I suspect most/all generators meant to block out noise do something similar. It really sounds pretty bad without that, especially for anything more than a few seconds.
Yeah. pink noise is often confused with white noise in audio because it looks flat on a lot of equaliser displayers (because they show energy per octave instead of energy per Hz).