That's not enough to say Gaara > Madara. Oh, and this is the wrong section. This should be in the Vs threads section. And Madara took on Kurama before along with Hashirama. Shukaku won't make a big difference.
dude,noone is saying gaara>madara. Gaara in this situation has a chance.
Shukaku dosent have skin,can use sand and wind techs. Also gaara's chakra will be massively improved,madara needed to go through several layers of susanoo to finally complete the susanoo n their fight. This is also a dessert,meaning sand under his feet. Madara's meteor isnt more powerful/destructive as a c3 nuclear bomb which gaara blocked witohut the aid of shukaku. Gaara on his own already tanked a meteor,according to OP,he is in sync with his bijuu,meaning genjutsu is pointless,madara's moukton can be levelled with a sand tsunami in his shukaku copy form,tree flower world is beaten by the above,or drilling air bullets. His dad stated that gaara himself was using his sand on the level of the mini shukaku form when he used to stop his rampage,which was when gaara was 12,so current gaara with shukaku will skyrock his sand powers immensely. 25 moukton clones are beaten by tbb,or ust brute force,5 of them couldnt break gaara's sand while he wasnt looking,25 arent touching a skyscraper level entity with hundreds of tons of sand packed with chakra many times higher and stronger than gaara,but madara only did that bcos it was 5 on one,so it is unlikely here.preta is useless,cuz the shuaku controlls sand without chakra,amaterasu and katon are useless here gaara can make several copies of shukaku to fight for him as well. Now that he has shukaku,gaara dosen need onoki's help to pull him out of his incomplete susanoo and seal him,but madara would probably escape that one. His complete susanoo isnt really a problem for the shukaku in the dessert,his sword isnt gonna pierce it,but a tbb can break it.his perfect susanoo is the main deal here,i think shukaku would be either equal or a bit bigger than that,we don't know it's tannking prowess,but i don't think it can tank a tbb. I am assuming this madara is IC,which means he wil probably start without susanoo and use taijutsu/kenjutsu as an opening which is quite pointless. If this was alive madara with these abilities,then it would have been a different story,cuz perfect susanoo will drain his chakra like a straw. However madara plays around and underestimates his opponents too much,his ams ado form was beaten by a weakened gaara and a naruto clone in base because he was too full of himself. If gaara can capitalize on this weakness of madara quickly,then he has a fair chance.
All in all i think gaara has a chance,it's not like all the kages are using their top techs,they are all nerfed in some way. Mei can't use her more deadly jutsus bcos of collateral damage,onoki is very old,raikage has one arm and is past his prime,gaara can't use his more powerful AOE techs because of the others getting trapped,tsunade's last taste of battle is i part 1,and before that,20 years ago. Konan managed to hurt tobi more than what team naruto is doing now,does that mean she can beat any of them?.
I am not saying gaara wins,just that he isnt raped as easily as you think.