While there are many causes of the development of portfolio careers, the main driver is technological advancement: social networks, remote work, online market-places, and cloud computing, among other innovations.
Looking back, that there was no social media between 1993-1996 was both a blessing and a curse, as that is when I was the lead singer / co-conspirator in a couple of bands.
The FUSE
A four-piece rock outfit with funk undertones, with Romesh W. on guitar, Wendel L. on drums, Mark G. on bass and me on vocals. After rocking pubs mainly in Adelaide and Melbourne, we relased an album of mainly oringal songs named Catalytic Influence.
FRET
Romesh and I got great experience performing live two or three nights a week in pubs, clubs, hotels, and even played a wedding or two, mainly covers of classic rock and pop songs, on accoustic guitars with some percussion and saxophone added occasionally.