Connecting the topic of open source funding with the topic of security: perhaps, companies should pay the authors of the open source packages? If you can pay, at least, you know who the author is and if she/he is a real person, thus, establishing a certain level of trust. And everyone benefits!
If you’re not working on a greenfield project, rather converting an existing one to Flow, that is absolutely a great reason to use Flow over TypeScript. Getting type coverage up as quickly as possible is really important for the peace of mind using a type system provides.