Not at the scale YouTube operates; the maybe 100k english creators (and a million more elsewhere) that have a full-time job doing content creation wouldn't have it without YT's discoverability algorithm.
There seems no way to prove or disprove that statement, since the evolution of the web created this reality and a different reality never got tested.
The current reality arguably depended on significant forks in the road of history, at least some of which might have been somewhat random.
For example, in a different, less monopolistic, version of evolution, there might be twice as many content creators, each making about half as much money.
