CMR has been one of the worst possible fonts that proliferated throughout the academic world. I don't understand it, perhaps it's just me, but there are dozens of other fonts that are more readable on paper and on screen.

There's just something very wrong about the glyphs, the relative widths of letters, and the way that some of the letters get sort of squished together to make the text nearly unreadable.

I remember way back in the 1990's when I had to get an approval from the head of our department to submit my thesis in another font because I refused to use CMR.