Bill Gates was a much more influential to a wider variety of computers well before the Amiga was out. For instance, the PET, VIC-20, Apple II, TRS-80, C64, PC, MSX, etc. all used his version of BASIC. Plus, I think what the magazine article is about is the charitable work that his foundation does which Jay certainly never had the money to do.
Nothing against Jay Miner, of course he did create the computer I love.