I used to work in a paint lab. Things things that also affect perceived color include:

- Undercoat color

- Number of coats

- Gloss Level

- Size of colored area

- Surrounding Colour

- Combination of tinters used by each brand. (Different tinters can make colours metameric)

- Light Source (Incandescent, D65, LED, Fluorescent)

- Monitor Color Space (sRGB, DCI-P3)

- Color Space / Model used for conversion (Lab, Luv, Lch)

- Colour Difference dE Model Used (CIE76, CMC, CIE00)

- Precision and spectral range of the spectrophotometer used.

Etc