[tarikjn]

I think it actually makes a lot of sense, from a computer architecture point of view: (1) total resolution is generally a component of the graphic processing power needed (for straightforward graphics rendering), and so scaling GPU power with displays/resolution make sense (2) placing a GPU in the display lower the demands on the interface, of which Apple has repeatedly hit the limits on

In addition/as a result of these you get some usability and user experience advantages: (a) avoiding degrading laptop performance when connecting an external display without the user having to know about eGPUs (b) no additional box/cables/power mess from using an eGPU

[amelius]

And cooling can be easier through a large flat surface too. In fact that could be one of the main reasons.