How many times must a man look up Before he can see the sky?

'The fact that its popularity has not greatly diminished over time can perhaps be attributed to the fact that while the song asks these questions, it does not refer specifically to any particular political event.' I'm talking about the song "Blowing in the wind" by Bob Dylan.

'In 1975, the song was included as poetry in a new high school English textbook in Sri Lanka. The textbook caused controversy because it replaced Shakespeare's work with Dylan's.'

My point is how can you compare Shakespeare’s work with Dylan’s? I’m confused. I mean its two diverse scenarios. But when I was schooling I choose to study literature because of these poems (or songs or whatever you want to call it) like ‘Blowing in the wind’ and ‘Eleanor Rigby’, but not because of ‘Shall I compare thee to a summer's day?’
I’m not saying that I don’t like Shakespeare’s work. But that’s how I felt about it at that time.