Aggregation is pretty much their core value proposition.
How could they "underestimate" this?
Because it turns out that aggregation isn't much of a business. If Patreon decides to maintain their current business model (and that is their main value to me), I don't know whether they'll actually go bust, or just be economically moribund, but either way, it turns out that there's not money in being the sort of business I need.
It's much like KickStarter started out as an Arts funding model, but eventually realized that their real value to people was as a pre-order house. Allowing people like me to support artistic creators might sound wonderful, but it's pretty much a loser's game. The customers of any real worth have enough money for real subscription services.
(It's sort of like when I finally realized that my small donations to charities were financially worthless to the charity - they literally spent more raising than I was willing to give. The worth of my donation was solely its help in providing the appearance of widespread support, which was necessary for the charity to get the real donations they were looking needed to do anything useful - those in the $100K+ range. My job was simply to help them establish credibility to the real donors.)
So, yes, we helped Patreon establish the credibility it needs to become a subscription business. But we have to face the fact that most of us are financially worthless to the businesses we'd like to serve us.