This is so true, in my experience. You hit a roadblock in recurring revenue, not because your product doesn't have enough features, or your team sucks, but simply: your market is smaller than you thought.
Don't take that as a slight to Gumroad either. Building a profitable business from almost going under and now generating close to $1m in annual profits is an incredible feat. But I do disagree with the point that the market wasn't ready (as clearly demonstrated by the success of others).
That's why everyone was up in arms about the fee change in 2017. People tossing $1 here and there to people they liked were the foundation of everything. Membership businesses generally start at $5 a month.
And Patreon isn't going to have much luck with it. There are so many better options if someone just wants to set up a membership business. Memberful, which they bought, wasn't even one of the better options. It doesn't even handle anything other than plans, payments, and integrations with services that do the heavy lifting.