I am gonna have to call b.s. on zep.
Gonna have to say Queen.
Freddy Mercury embodied the rock and roll front man.
Beyond that, queens musical style was far more varied and their sound was much more polished.
Head to head skills, Bonham beats Taylor and page beats may..sure.
But the sum is greater than the parts with queen and Freddie has possibly the all time greatest rock voice. His clarity and pitch are beyond compare.
Zep is legendary for sure, but if i am allowed to put one band in a time capsule to be opened 1000 years from now, queen has the greater body of work, better sound, and is the prime example of rock and roll showmanship.
*disclaimer- neither is in my top faves...more of a metal head.
My opinion is solely based on range, showmanship, and polish.
Zeppelin and their rougher sound and lesser production slides towards the edge of hard rock in their time period.
Queen sits solidly center of rock and roll imo.