The business model for OS has been really tough historically, which probably has made raising money harder, so growing as rapidly as the SAAS companies therefore really hard.

It's quickly becoming clear (GitLab/Mattermost/Sentry) that there are some great ways to build enormous companies like this though. And, that's of course assuming you want to build a huge company :)

At a personal level, we found that this kind of business is just more fun to build... making cool stuff in the open and if we do a good job, getting inbound interest from bigger companies that have developers who need to use our tech at scale.

I don't think it'd work for everything - if you are a tool that developers don't interact with much, then I'd imagine it's tougher to build a real community.