Yeah, I guess in the 70s the meaning was totally different than in the 20s. In the 70s the meaning was that those in the Great Crowd would never die.
In the 20s when the campaign identified by that slogan was going on, there was no such thing as the Great Crowd.
Fact is, those people in 1935 who stood up (according to the Revelation Climax book) to identify themselves as members of the GC were promised they would never die. In reality, they were no better off than some cannibal in Sumatra (who died and will be resurrected just like those early GC dopes).