Madara's early revival would only make everyone wary of him. His every move would be watched. Not only would there be no benefit, it would only bring piles of trouble.
Otherwise, in the original story, why hadn't Akatsuki simply taken the easy route and revived Madara directly, then continued carrying out the Infinite Tsukuyomi plan? What they feared was something going wrong. Having other people do these things was safer. Although Obito had been running around everywhere under Madara's name, how many people truly believed him?
Whether he was worth believing aside, Akatsuki's operations were basically conducted in the shadows. Only after the plan to capture the tailed beasts began did they slowly surface. With Madara's personality, there was no way he would act like that. He would definitely swagger straight into other people's villages and seize the tailed beasts by force. If that happened, how could the Infinite Tsukuyomi plan ever be realized?
Even though Madara's strength could crush every major village.
In the current Ninja World, if Uchiha Madara were revived and took back the Rinnegan that belonged to him, he would be practically invincible. Only Ronglin could contend with him. But doing that would only make the Infinite Tsukuyomi plan harder to realize.
They could not revive Madara ahead of time, but they also needed to guard against Ronglin. So Black Zetsu came up with an idea: before Akatsuki had fully accumulated its strength, they would cause major incidents in the Ninja World and draw Ronglin's attention elsewhere.
Even now, Black Zetsu was still working tirelessly for the Infinite Tsukuyomi plan. The plan to capture the tailed beasts had already been put on the agenda, but the Nine-Tails was not among the targets. At this point, no matter what Akatsuki did, they would try their best to