Why does latex not have /magnification?

Why does latex not havee the equivalent of the \magnification command in
tex? From what I read, you can use [10pt], [11pt] or [12pt] commands
(and no bigger) or use the slides class but that hardly makes up the
flexibility of the magnification in tex.

On a slightly tangential topic, why are the number so horrible in the
slides class? (the superscripts especially for the numbers become a too
large san serif set of ugly numbers in the slides class)