You are correct, most Linux distros and kernels are not open source. Very fucked up to blame F-Droid for that while you keep lying The FOSS Linux kernel is open source and there are FOSS Linux distros Many closed source Linux distros also lie about being open source And it's often beyond simply changing binary signatures for every build - it's actually including proprietary stuff even in the public repos (but still often trying to gaslight users to call it "open source" without qualifiers)

I didn't say distros or other kernels. I said Linux itself. F-droid cannot compile the core kernel from Linus himself.