Sony - I think the best first party Sony game is God of War 2018. I think it epitomizes what Sony games are about. Creating great characters, narratives, while also being filled with action and fun.
Xbox - Didn't play Halo at its peak, so I might be missing out, but for me, Forza Horizon 5. Playground Games is the only real consistent AAA developer MS has. I look forward to Fable!
Nintendo - 1st party is much the reason why you get a Nintendo system lol. So many great ones to choose from, but Ocarina of Time still takes the cake for me.
What about you, SW? What is the best first party game Sony, Nintendo, Xbox have ever made?