You guys are jumping the gun. Luffy was saved from death three times in that fight.
There isn't a single character right now who could match Imu's performance: fighting Loki alone, then Luffy, then Gaban, and now taking on three or four opponents simultaneously—assuming Gaban stays in the fight.
Not to mention that since arriving in Elbaf, it’s been stated that Imu isn't at 100% and can't stay away from Mariejoa for too long.
On top of that, Imu controls the five Gorosei and the Holy Knights, can instantly teleport anywhere in the world that has a seal, and possesses an unrevealed power capable of destroying an island in seconds—yet for some, that still isn't enough.
It’s funny how people worship someone who ran away from Shanks at Marineford, ran from Akainu (who was alone), was afraid to face Aokiji, ran from Rayleigh, and needed help against Law.
Yet now, someone fighting three Yonko-level opponents single-handedly still isn't enough.