This means you can only really make money on support (and not the software itself), which doesn't scale well with one or two people (also the reason so many open source projects are abandoned). With this model, only very large companies can survive (Amazon, Google, Redhat, etc).
Years ago, I had an open source project with a paid component. Most in the open source community not only didn't want to pay, I would actively receive nasty emails for trying to make money on my own project.
something interesting you will notice even with those companies---GitLab, Hasura, Strapi, even Cal.com come to mind---is that they too get flak for feature-flagging, restricting paid features to closed repos for a period, and making choices that help them sustain. the beginning of open source led to a synonymization of the term with everything-free-forever and it continues despite the number of projects that have died or tuned closed-source and the founders that have stopped maintaining their repos.
weird how we'd much rather have projects die than advocate for their sustainability, but it is what it is.