Text in all capitals has no ascenders or descenders to give each word its shape, so many readers take it letter by letter. That cost falls hardest on people with dyslexia or low vision. Some screen readers also spell out a capitalized word as if it were an abbreviation.
Small caps count too
Small caps look gentler, but they have the same even outline. So this kit leaves them out as well.
What replaces them
A label is still one or two words. It stands out through its weight, its place in the grid, and copper. That turns out to be enough.