I think this is a perfect read for anyone contemplating on starting their own business as this clearly illustrates that not every startup is destined to become a unicorn and/or should be heavily backed by VCs. Moreover, if that is the only reason why you are pursuing your venture, then you will most likely experience heavy turbulence, possibly face the brink of total failure, and possibly just have to accept failure.
All that being said, I really enjoyed the end of the post, where he was explaining his change in outlook and open-sourcing the service. This could lead to wider adoption and potentially open new sources of revenue, similar to Discourse and how they can create and manage your forum for a fee even though the product itself is open-sourced. The reality is, sometimes people need the middle-man and it is nice to have the option available if you are in that situation.
Thanks again for sharing your experiences. I wish Sahil and the Gumroad team all the best :)