Why did bill gates been accused as a thief?

Answer 1

because people seemed to be biased toward apple or biased against microsoft,

People seem to believe that Microsoft stole the idea of a GUI (Windows, menus, mouse, etc...) from apple and accuse Microsoft (and thus Bill Gates) of being a theif

However, the GUI as we know it (windows, menus and a mouse) was not invented by Apple or Microsoft, but by the Xerox Palo Alto Research Center, Steve Jobs and Bill Gates both toured it and went back and developed there own version, with Apple releasing a product first, Microsoft also struck a deal with Apple that licensed some of apple ideas, which licensing is not stealing.

There was that time when Microsoft was sued by Digital Research, it was proved that PC-DOS was a CP/M clone