I think saying that basing a console on PC hardware is being "lazy" is very narrow minded.
The point is that costs have been constantly going up and if developers say they need thing to be easier you would be a fool to ignore them.
You also make it sound like neither Sony or Microsoft did any customisation at all which is not true. They did exactly what Nintendo did, started with off-the-shelf designs and revised them accordingly. The PS4 has a custom network processor and DSP, the Xbox One also has a custom DSP although arguably sticks much closer to the PC design - but as the company who makes Windows that is hardly surprising.
Consoles were custom because they had to be, PCs were very inefficient and this has slowly improved. Nintendo stick with custom because it means exclusive titles have a huge advantage, but that is also why their key titles have taken so long to come out on Wii U. Its also really annoyed the third-parties which is hardly a logical business decision.
So if anything, I would say its Nintendo that are shooting themselves in the foot here stubbornly refusing to change with the times.