This passage from Revelation-Its Grand Climax! is what caused me to take a second look at the WT doctrine that the 144,000 are a heavenly class, and the remnant of said class is associated with WBTS.
The 24 elders and the anointed group of 144,000 are described as being "round about the throne" of Jehovah and "upon the [heavenly] Mount Zion." (Revelation 4:4; 14:1) The great crowd is not a priestly class and does not attain to that exalted position. True, it is later described at Revelation 7:15 as serving God "in his temple." But this temple does not refer to the inner sanctuary, the Most Holy. Rather, it is the earthly courtyard of God's spiritual temple.
The point about the Great Crowd not attaining to that exalted position is, imo, a way of saying, "na na da boo boo, we're better than the rest of you!"
What a bunch of self-aggrandizing losers!
Sylvia