Your eyes don’t deceive you. BM Onyx is a very dark, extremely near neutral ‘black’, from the RED Hue Family.

Every, Black, white, grey, near neutral paint along with more colourful colours, can be measured so we know to which Hue Family it belongs.

BM Onyx sits at 21° on the Color Strategist Wheel. Even this low in Chroma (colourfulness), you still have moments where you are able to detect the influence of its parent Hue.

Here are some other very dark near neutrals suggested when someone was looking for one to work with White Dove. Finding a ‘black’ from the same Hue Family as another key finish in your space, creates a sense of harmony, as they are related.

Another classic strategy is to choose a black from the opposite or complementary Hue Family to a key fixed finish in the space for an extra kick of contrast.

IMO what makes this a warm black is the fact there is a bit of brown in the mix. I honestly have never used a chroma # to decide any color in any space . I think it is a guide but not gospel . I like the choices in your post but the true test is what is it like in your space with your lighting . I advise kitchen lighting to be all LEDs 4000K to mimic daylight before choosing colors that are difficult to change once they are in. Like flooring, cabinet and counters.

If you see it now, certain times of the day you will keep seeing it.

I see grey!