Hello? Okay two things.Uchihas natural element is fire yet Madara could use wood release just having Hashi boob .
Who said that he cant ? He has all requirements for that.
One. Madara has the rinnegan which allows one to master all ninjutsu potentially including elemental ninjutsu. In fact, when Madara was alove his only mokuton feat was when he had the rinnegan. The other times was when he was an edo tensei but even Kabuto already stated he made major modifications to his body which allowed him to use mokuton. The sharnningan cannot naturally copy kekkei genkai such as a combination nature such as wood or storm release. Although the rinnegan can. Heck even when Madaravwas brought back to life he showed zero mokuton feats and just used susamo otherwise he would use the wood dragon instead of limbo to restrain the bijuu pls don't confuse manga facts.
And two. Madara had a large portion of hashi's chakra attached to close to his heart, you know the organ that pumps cells throughout the body??? Naruto had to placed on his hand, that doesn't mean he can use wood style heck orochimaru's enture body was composed of hashi cells but he wasn't using mokuton...