They may have started to write more pop, but they were still producing songs from their progressive roots. To support the point, Duke's Travels/Duke's End, Home By The Sea/Second Home By The Sea, Domino, and Fading Lights are definitely not pop!
And Naminanu, Submarine, and Do the Neurotic, in addition to quality “popish” songs like Evidence of Autumn, On the Shoreline, You Might Recall, and Feeding the Fire. They were writing and recording plenty of quality, substantive music. Unfortunately many of those songs weren’t included on the albums that directly came out of those various sessions.