The laptops that are being discussed all have GTX 960s or 970s. There is no need to have a slightly better integrated GPU if you are using these higher end discreet gpus. Not only that, these machines cost less with these GPUs than a 15" MBP with only intel integrated graphics and 3 year old hardware.
That's circular reasoning — Apple never intended to use those chipsets, so why bother talking about other manufacturers who are using them and how much they cost, to prove Apple is late in doing something they were never going to do?
In the MBP, Apple uses either the Iris Pro only or Iris Pro + dGPU on the high end. Everyone has been expecting them to use the Iris Pro 580 chipsets since they were announced in January based on the past, which are just now coming out.. All signs point to them continuing to use AMD, who just now released their Polaris line.
Just because some other manufacturer is doing stuff another way doesn't mean Apple should do the same... so what's the point of saying "so and so released this totally different configuration and it's been out for x long" when all signs point to Apple not ever planning to do the same? You think Apple doesn't consider their options thoroughly before deciding on what to do?