No, it is not your imagination. Pop music really is getting less colorful, less intellectual, less varied, less diverse, less interesting all the time. That did not just happen. It is the result of major trends in the music industry.
This is a lengthy video -- about 20 minutes. But it is well worth a listen, as it may explain many things you have been feeling, but never put into words.
Of course, there are many true artists creating brilliant music today, but they rarely enjoy the support of the new music industry. Urban Renewal Jazz is proud to be associated with such real artists.