You're the most logical person to disagree so far. But dont you think that he contributed to madara becoming evil? Cus it looked like Madara was gonna cooperate with Hashirama when they just built the village, just until everything in chapter 625 happened. In short, Tobirama caused the Uchiha to become a clan that had to be watched over.
Thanks there bud
I think the reason is mainly on Madara's shoulders, although Tobirama wasn't really a help in the situation.
After the Senju and Uchiha swore allegiance with one another the Uchiha became the Police force of Konoha, and the Uchiha were fine with it, except for Madara.
He felt the Uchiha were above that, and asked his clan to help him with a new change, but none joined him.
Tobirama from the alliance onwards knew Madara was a casualty to the Leaf's progress and declined the idea of Madara becoming Hokage due to his ego, and issues in general.
Was it wrong for Tobirama to be overly harsh over Madara? Yes.
Was it for the best that he didn't want Madara to be Hokage? Yes.