I still don’t understand why none of my art teachers ever told us this.
Once we had Newton’s discovery of the color spectrum in white light. We could began to understand the difference between additive and subtractive color theory. Because the painters primaries were established long before we understood how light worked they are RYB. This is an additive process. RGB which is the color theory used by computers, TVs, and cameras is a subtractive process and mimics the way the human eye sees color. CMYK which is used in printing is an additive process. So yes it makes a nicer quality color. But the reason your art teacher never says to use it is because of historical context.
TLDR: Because the painters primaries (RYB) are different than printers primaries (CMYK). Which is different still from digital primaries (RGB).