Maybe it has, or maybe wages are not the same, or it's not really the same product. I'm a jazz musician, and my gig pay has stayed steady at about $100/night for 40 years, though my skill has improved. A lot of people who would have been classical musicians during the classical period are now working as church musicians for peanuts, or playing for free. Musicians playing in front of crowds of thousands didn't exist during the classical period -- the instruments weren't loud enough yet. And "classical" music has gotten harder to play.
The article mentions teachers. My teacher taught me BASIC. Today's teacher teaches Python, which is considerably more productive and valuable. College is increasingly being taught by adjuncts.
Doctors and nurses. A century ago they mostly poisoned people. Today, my primary care clinic has a "doctor" who oversees multiple nurse-practitioners and nurses, and who I see only once a year.