Not always, for example original CD disks had capacity of 74 minutes to accommodate Beethoven's Ninth Symphony.
That one also turned out a myth :) CD size was determined by Cassette tape dimensions (diagonal, human can still hold one in one hand) and that combined with conservative pits/lands/track pitch choice drove the play time.
thus CD runtime was derived from something "what we had at the time".
loading story #47392490