When converting these to runtime sprites (which is how modern games and game engines render fonts) the empty whitespace ends up being transparent pixel overdraw, very bad for performance. Essentially you want the quads the correspond to the letters to be as small as possible, every pixel rendered (including transparent ones) costs GPU time.
I'm not speaking for tcsc, but I am speaking for myself and honestly all games that runtime render fonts. The extra computation would happen in 2D pixel-by-pixel rendering as well.