I've heard this analogy regurgitated multiple times now, and I wish people would not.

It's true that many master artists had workshops with apprenticeships. Because they were a trade.

By the time you were helping to paint portraits, you'd spent maybe a decade learning techniques and skill and doing the unimportant parts and working your way up from there.

It wasn't a half-assed, slop some paint around and let the master come fix it later. The people doing things like portrait work or copies of works were highly skilled and experienced.

Typing "an army of Garfields storming the beach at Normandy" into a website is not the same.