We press play, don't press pause
Progress, march on!
Things have to keep moving forward, not stopping.
This could also be a reference to the phrase “pause” which people often say to assert their heterosexuality when they say something that could be misconstrued as being homosexual, i.e., “suspect” as some say.
Here Macklemore is saying stop saying “pause” because all people are equal and being gay isn’t a bad thing so one needn’t say pause. Instead “press play” which means to move forward. Thus “progress, march on”.
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