That was Spielberg idea, so unless bruce timm still land to work with warner...that is butterfly away
I don't see why Timm wouldn't still end up at WB. The fact that they didn't buy DC probably wouldn't butterfly that.
One thing that WOULD be butterflied though is this. While I don't see Tim Burton attempting to make a Captain America movie in place of Superman Lives, I do see him trying and succeeding in making an FF or Hulk movie in its stead.