It’s not wrong. There is no absolute 000000 and FFFFFF. It’s relative to a white point and tone curve.
Of course, when you do color grading you want to have those fixed to whatever standard you are working with. But then you also have to control your ambient lighting accordingly, to get the correct impression of what you’re seeing. Even then, IPS displays aren’t capable of displaying true 000000, due to their backlight, or only very coarse-grained with local dimming zones.
Most people aren’t doing that kind of work, however.
