I don't see the OSS world as transactional. For example, I contribute some modest OSS projects for free without expectation of direct compensation. Lots of other people do similar things. That's what makes OSS work.

Some of that stuff is supported by big corporations that employ the people that work on those things and have a financial interest in making sure those things continue to exist. As a result, I get to stand on the shoulders of giants. That extends to things like Linux, databases and other middleware, frameworks and libraries, and lots and lots of developer tools.

I pay for plenty of SAAS stuff when I need to or when it adds value. Just not for Intellij.