Really hard to classify anything from a huge band like LZ or the Beatles in my opinion. Fanatics and historians have picked apart those catalogs from every possible angle. Pink Floyd is odd in that very few of their albums are super accessible or well known by non fans, yet the ones that are known are damn nearly universal. Helps tremendously that AOR in the late 60s into the 70s was very free form and largely on AM which meant fewer people listening. There's an old saying in radio, "niche formats get niche signals" and as rock evolved and became more prolific and less niche it moved over to FM and shorter songs became more valuable.