That's because Intel insists on doing everything in-house. AMD and Nvidia went towards TSMC as they have the best technology. Meanwhile, Intel have been lagging behind and their new architecture keeps being delayed.
Their answer has been to keep pumping more voltage in their chips so that they can hit bigger numbers making them more and more inefficient. The bigger problem is that now their high-end chips are unstable as the insane amounts of voltage are destroying them prematurely. It's just a mess.