read as: Good enough for those not doing any own software development and/or bugreporting.

With closed source parts of your system you can never be sure where the rare crash came from. You cannot recompile the driver with safety barriers (_FORTIFY_SOURCE, mudflap, valgrind...), hardware watchpoints trap in binary code you cannot easily verify...

This results in unstable software commonly found on closed source platforms as nobody can provide reliable software there.

SIP (its STUN support works only with a luck).

Besides any service providing = servers which I run some for local stuff even on my notebook.

So I have to square root the billion pixels first and guess the painting size or guess the parameters of "an average digital camera"... Why they just cannot say the DPI? slashdot is a technical magazine or - ok, it is no longer.

So what's left of GNU code now?

Choose any two GNU packages on your system. That is still more than that one Linux kernel.

what is wrong (philosophically, security-wise, or wishing leprosy on oneself, etc.) with installing Moonlight

That you may get sued (=Fedora forbidden item).