I think that this book was published in 1963 and maybe the message 'millions now living' may have had some relevance with,
'the combined number of Kingdom advertisers around the earth numbered more than a million in April. — Revelation 7:9,10.' ("Babylon The Great Has Fallen!" God's Kingdom Rules!)
but not sure that it would now.
I think this Cedar Point Ohio mentioned in the quote is also the when the sounding of the seven trumpets got under way according to them.