That's incorrect. As the original author of the work, you can release the project under whatever license you choose. Doing so may make it impossible for someone else to meaningfully comply with it, but that's their problem, not yours. It doesn't stop you from choosing the GPL, even if it's a bizarre option for that particular project.
>>> At this point I'd include some of the code as binary blobs and "pay me for the source!". In addition to GPL!
So, the proposal is to hide the source code and IIUC if someone does this, the whole complete project can not be released as GPL.