Variable Fonts Explained

Great explanation! Cant wait to dive into variable fonts

Optical Size is meant to be set to font size, so if the boldness has too much or too little stroke contrast at the correct Optical Size, you should use the YOPQ or XOPQ or GRAD axes to finesse your font style.

In this case, your text was already at a very large size, so the large optical size looks better - but please don't recommend setting the optical size axis to a value that isn't the font size in pt :)