The biggest difference to me between the old patronage systems and the current ones is the class of people who are performing the patronage and the class of people recieving it. IIRC, patronage systems of the old times were mostly under the wealthy, and thus it largely prevents artists from producing against the interests of the wealthy. While the notion that one still needs to respect their source of income still exists in Patreon, Twitch, etc. the set of all possible patrons is more diverse, leading to a more diverse set of artists who can market to niches.The sorts of people who are supporting NK Jemisin are likely not the sorts of people who are supporting ChapoTrapHouse.