I agree it's not a perfect analogy, Wikipedia's model is even worse. Startups generate revenue as well. Wikipedia is nearly fully dependant on funding.
Wikipedia cannot "sell" their product, that's antithetical to it's purpose and mission. Doctors without Borders is not a failure because they rely on donations for disaster relief rather then profiting from it.
No one called Wikipedia or Doctors without Borders a failure. The article states that relying on donations is risky by nature, let alone when increasing expenses every year.
I would love to hear your thoughts on this, do you think there is no way donations may decline leaving Wikipedia in trouble with hundreds of people on it's pay roll?
The risk is that WMF decides, as the article presents, to sell off rather than downsize if donation revenue drops. Wikipedia itself can be sustained on 1% of the donation revenue the foundation is getting each year, so the only threat to Wikipedia is the foundation itself, not that there won't be enough money to keep it maintained, independent, and unmonetized.