What is it that unites these six bands?: The Beatles, Rolling Stones, The Who, Pink Floyd, Led Zeppelin, and Queen

No this isn't a riddle.

I don't remember where I read it, but these bands seem to constitute something of a "Big six" or are often listed together.

There's some broad uniting features: They're all iconic British bands. All the bands are considered contenders for "Greatest Band Of All Time", many of them in the top 10 or even top 5. All of them are now Classic Rock staples.

They're all very commercially successful with five of them being among the very best-selling bands/artists of all time.

Individual band members have their own levels of acclaim, whether it be with greatest frontpeople, guitarists, bassists, drummers, etc.

Examples: Frontpeople like Mick Jagger, Freddie Mercury, Roger Daltrey, Robert Plant, Lennon/McCartney. Guitarists like Keith Richards, Jimmy Page, Brian May, Pete Townshend, David Gilmour. Drummers like Keith Moon, John Bonham, Ringo Starr...

But upon closer examination, it's hard for me to find much that really unites them. Only three of them are from the British Invasion. Their years of dominance all vary from the 60s to the 70s, sometimes to the 80s. Queen for instance: despite some predecessor bands, they really got started in the 70s with their debut album released in 1973. So they're pretty late to the group.

Some bands were more favored by rock critics while others took a while to be reevaluated.

I don't know...it's this strange feeling where based on familiarity, it makes sense for them be listed together. But actually looking at their history and trajectory, they seem quite different. But it's not like you can just sneak The Clash into that group either. The Kinks were part of the British Invasion alongside The Beatles/Stones/Who but they're not really part of this "Big Six" for whatever reason.

Anyway: Is there something deeper that unites them or are they just an arbitrary grouping of successful British bands?