What works for creators (something like Patreon) won't work for Medium in this case. Medium needs to profit in a substantial way, and billing millions of credit cards every month seems the only way to get there. The clap-funding thing is just an attempt at including creators so they don't stop using Medium.

But, as a product, Medium is only a nice-to-have. My willingness to support my favorite writers is wholly disconnected from an interest in paying Medium for access.

If they hadn't taken so much money, Medium could be funded like Wikipedia. My $5/mo would feel better spent if it were helping fund the operation as opposed to propping up a billionaire's latest experiment.

That said, maybe we should all just be thankful Medium isn't trying to solve their problem with an ICO.