I've beaten Route A of Nier:Automata today. So next is Route B, a.k.a. the reason a lot of players missed the true ending of the game. And I won't blame anyone, I almost stopped playing there, too.
My progress in Sparks of Hope has been minimal, but I hope to finish World 2 this weekend.
Techically 3, I would say 2 and a half. Route B is mostly the same as Route A, except you play a different character. Many people stopped playing, thinking it was just a bonus, and completely missed that Route C afterwards is a continuation of the story.