Oh yeah, it was quite stupid of Tramiel and the ramifications were something Atari never was able to recover from. It is fun to imagine how things would have been different had they licensed the NES and either launched it themselves or let it sit on a shelf somewhere for a period of time - at least postponing the launch of the NES in North America.
I believe the gaming world would be more than slightly different had they done that.
RE: Atari Shuts Down the 7800 – Today in History – January 1st, 1992