I also agree that Pink Floyd was a better all-around band, though I'd put Deep Purple ahead of Sabbath in the ranking. I'd put all three ahead of Zeppelin but we cannot deny Zeppelin's 110+ million albums sold in the US, bested only by The Beatles, Garth Brooks, Elvis Presley, and The Eagles.
Zep put out two great studio albums, both dominated by Jon Bonham...#1 and Physical Graffitti. The rest of their albums span from mediocre to lousy.
I saw them twice live.
The sucked both times, and I mean sucked.
Saw both Sabbath and Floyd live twice too. Both times they both burned the house down, leaving all who attended simply stunned with wonderment.
I assume this is the show you are referring to.
Jimmy Page had the best rhythm section since Cream and still is arrhythmic with them. Simply Bizarre.
https://www.youtube.com/watch?v=DohsUDR7otk
From the same year, here is a superior band. Tighter. More melodic. Synchronized and TIGHT.
And far, far better song writing.
https://www.youtube.com/watch?v=FeVzUGhPpCQ
Peter Grant threatened Grand Funk Railroad's manager to force them to get off the tour with Zep because GFR was blowing them off the stage.