It doesn't excuse everything. But let's use Madonna as an example -- I think some of her songs are consciously and explicitly about political subjects. Is 'Music' consciously and explicitly about political subjects -- oh we've been there. Are Jane Austen novels consciously and explicitly about political subjects -- ah we've been there too. Clearly on this list we are not in agreement on what art is consciously and explicitly about political subjects. So I think your definition will not do.
Catherine