For all the people not reading the actual law, this is the actual language of the proposal:

In order not to hamper innovation or research, free and open-source software developed or supplied outside the course of a commercial activity should not be covered by this Regulation. This is in particular the case for software, including its source code and modified versions, that is openly shared and freely accessible, usable, modifiable and redistributable. In the context of software, a commercial activity might be characterized not only by charging a price for a product, but also by charging a price for technical support services, by providing a software platform through which the manufacturer monetises other services, or by the use of personal data for reasons other than exclusively for improving the security, compatibility or interoperability of the software.

IMO the problem OP mentions does not really exist. You can work for a corp while working on the product, your FOSS project can take donations even from corps, the only thing you can’t do is monetize your FOSS product without caring for security.