Your missing the point though. If Disney did not bankroll Pixar's first film someone else would have done it wether it was Fox, Universal, Sony, or New Line. Just because Disney was the one who financed it doesn't mean squat. Second while Lasseter was a Disney nut he was also a Lucasfilm nut and was heavily influenced by Star Wars. In fact he used to go around saying "I want to do the Star Wars trilogy equivalent in animation". And again aesthetically their movies are nothing alike (especially before the merger) and Pixar's culture which is director and creator oriented is very different from Disney's top down management style where suits determined what movies got put into development. I've seen the Pixar Story doc several times. It does not back your claims. Disney has as much in common with Pixar as it does with Lucasfilm, the Muppets, and Marvel. Frankly between those 4 Pixar is the least Disney to me IMO.
The argument is pointless though as all of those are considered branches of Disney. Case closed.