That is also mind-numbingly absurd to force upon the vast majority who couldn't care less about the bleeding edge and want a stable platform to act as a fixe target without risking random ABI breakages.
I should not be forced to endure a brittle and fragile and overly-complex compilation process just because a random guy somewhere had a whim about taking a compiler out for a spin.
The world expects stability. If you wish to try out some stuff, just download the compiler and build the damn thing yourself. Hell, odds are that there's already a PPA somewhere. So where's the need to screw over everyone?