Why aren't there or laptops and all in ones that use desktop graphics?

This shows it's completely possible to put a high end desktop GPU and CPU in a laptop/aio form factor.

So why haven't more pc builders done this, especially with reduced heat output and lower TDP in recent architectures?

If heat is still a problem I don't see why they can't remove the cooler on a desktop component and replace it with a slimed down version of closed loop water cooler and radiator.