Maybe I was not clear enough in my comment. And never talked about Medium as a side hustle.
On the contrary, I understand that it is one of the means to build a profitable and diversified network of passive incomes.
Yes, you have to write aggressively and persistently to keep your income stream.
But also, by building a personal online library, you are increasing your chances of having a passive income for something you already did: your previous posts keep producing money.
As can be an online course, a rental, stock photos, royalties, dividend-paying stocks.
So then, once you decide to retire, these passive income sources will keep producing.
Hope it's clear enough now.
Never meant to depreciate your work.
Quite the opposite.