Off the top of my head: Newsblur, Bitwarden and Standard Notes, services I pay for, for one because I like to support open source, but also because I'm not in the mood of hosting them myself. I'm also evaluating Wallabag.
These examples are of web apps that require hosting, self hosting is a pain, so I prefer to just pay for it. And I did give up on 1Password for Bitwarden, because I'd rather support open source stuff, in spite of the former being superior.
The author's article is however correct in saying that donations don't work. I too have thousands of stars collected on GitHub and I barely got donations for hosting the documentation websites.
In order to make money:
1. you have to ask for it
2. people need to get some value out of that payment and this means creating scarcity
With the online services I mentioned, what I'm paying for is the hosting and I'm happy to do it.