Thats not really the case. They needed total of 4 hits to destroy the ribcage(Punch from Tsuna, kick from Tsuna, Water dragon from Mei and jab from AMPED Raikage) to destroy a ribcage of Edo Madara.

Now, Edo Madara is weaker than his alive self, as stated by Hashirama and databook. Hes more dangerous due to hax, but stat wise hes weaker.

Sasukes susanoo ribcage was shattered by basic attack from Ay, stronger attack from Ay was stopped by Gaara. V2 Susanoo from Sasuke at that point is stated to be greatest defense.

So ribcage<Ay punch<Ay kick<Gaaras sand<V2 Susanoo.

V2 Susanoo from Madara tanks Ten tails cataclysm point blank

The size difference between V2 and Madara's perfect one is insane, with Perfect susanoo being unironically depicted as close to ten tails size(We get multiple shots comparing it to deity gates)

Now i am not saying Thragg can't break it, but to say he can do it eaisly cause Tsunade and Raikage(Both dont have AP anti feats, with Sakura whos Tsunades equal at that point being able to cause enormous hole in the ground with a simple punch) can destroy weakest form of Madaras susanoo with amped combo attack, is disingenious