the 7th chords, treated functionally are tensions which need to be solved, as a classical dominant-tonic movement. However, you find tones of 7th chords which are not solved in a upwards-perfect-4th-movement like this; i.e., they are not "solved". In fact, you may have a 7th-dominat leading to a major-7th-tonic, which isn't found in earlier works.
This might be a shallow explanation, but I hope it helped somehow^^