Back in the NES days, third parties actually did extremely well on the NES, especially if you break it down by region. For example Dragon Quest would sell the best Nintendo game in Japan and Ninja Turtles would sell like the best Nintendo game in the US.
Problem is that third parties don't want to be tied for the best. Rockstar likes that Sony has to kiss their ass. That makes things easier for Rockstar (or EA or Activision or whoever). But whenever Nintendo makes the best selling console, the third party games come anyway. Really it's better for the consumer that way. For me the best console was the NES, because it had all the best third party and first party games on the same system.