Originally Posted by
SrslySirius
The old fool says "This is old, therefore it is good."
The young fool says "This is new, therefore it is better."
Composers from the Romantic era and prior didn't write 3-minute songs. This came about because of engineering limitations with gramophone discs. It persisted because people got used to it and for the commercial reasons you noted.
But technology marches on. We got more efficient records, then tapes, then compact discs, and now digital storage and interwebs streaming. Radio becomes less relevant every day, and artists are less dependent on parasitic record companies. Musicians have been given more creative liberty to vary song lengths.
This is beginning to happen in the video medium as well. Web series and Netflix original programming are not restricted to specific lengths for advertising purposes nor do they need to force cliffhangers every episode for week-to-week viewing.
Call me a young fool, but I say it's better this way.