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A reminder in the age of the Fediverse: if you're not the customer, you're still the product.
(slrpnk.net)
OP was taking about Tumblr, but I think it applies even more to the Fediverse: users need to develop an ethos of paying to support the sites they use. Otherwise advertisers pay the bills and call the shots.
It would be nice to run some nodes attached to your favorite instance to distribute the bandwidth cost.