The problem as I understand it is that prior to natural-ness being in doubt, it was expected that the LHC would make discoveries in supersymmetry that would jus

The problem as I understand it is that prior to natural-ness being in doubt, it was expected that the LHC would make discoveries in supersymmetry that would justify practically bigger (but hugely expensive) colliders. Without a new frontier of supersymmetrical particles to explore, that next collider doesn't offer much for anyone to get excited about, let alone the taxpayers who might be asked to pay for it.