I think there are more ways to make money from open source than that blog post lays out. I thought the SFOSC docs do a good job surveying the possible business models with open source -> https://sfosc.org/docs/book/business-models/

IMHO, the "free software product" model and/or the OpenSaaS model are the two strongest choices. They both seem to have healthy revenue generation potential, while allowing a community to form and develop around the software.