Why should open-source projects shoulder the cost of "every single financial system"? These are run by for-profit companies. They can pay for running their soft

Why should open-source projects shoulder the cost of "every single financial system"? These are run by for-profit companies. They can pay for running their software, or the can open source their stuff. Right now, they try to externalize their cost and keep the profits. That makes sense for them if they can pull it off, but it's a clear downside to the affected projects.