My previous reply wasn't clear. It wasn't the difference between the meanings of open source and free software that changed my mind. It was the terminology change that helped rid me of the mental image of working for free. Now I realize there is a world of difference between free and open source software, but I didn't know that at the time.

As for now, I think free software is good for business. My company works on dozens of free libraries, and it's good for our business because we end up running better code than what we could write by ourselves. When you consider whether it is "good for business", you need to consider that most businesses don't sell software. Of course GitLab and others won't ever be able to sell free software, but that doesn't mean it isn't good for business.

I have mixed feelings about open source projects that are built by single companies who sell enterprise versions. It's often handy to have them around, but I wouldn't consider contributing anything significant to them after seeing instances where PRs remain unmerged because they compete with the enterprise-version.