Maybe because Led Zeppelin lll was a disappointment given how great ll was and IV deserves a tribute of its own.
When I heard IV, I kinda felt I would never look at life the same. Went and read Lord of the Rings. Then when ‘Houses of the Holy’ came out I thought “well, that was fun while it lasted”.
The arrival of ‘Physical Graffiti’ transported me to a sacred place…..or maybe, just maybe, it was the drugs. I’m not sure.