In terms of developments in pop music, the gap between pop music and the industry around it from 1964 and 1968 is greater than that between 1972 and 2016.
Definitely, if The Beatles (at the dawn of magazines like Crawdaddy and Rolling Stones and Oz, remember), in 1968, put out a song, a few months after Enoch Powell's 'Rivers of Blood' speech, called 'Blackbird', it's impossible to believe any adult wouldn't think, 'hmmm, nice song, Paul, hmmm, 'Blackbird', wonder if he's hinting at something other than one of our little feathered friends?'
The reason why it wasn't the hottest topic when the White Album came out is probably because there were 29 other songs to take in (i.e. the size of Amy Winehouse's whole career!), John had just taken his kit off for 'Two Virgins,' and by January, they were encamped in Twickenham Studios and the time (quick moving time the 60s - absolutely NOT like the music scene today) had largely gone.