Well, to be fair, Intel HD graphics is a lot better than GMA. With Crystal Well, it's actually pretty close to something like a GTX 750 and outperforms even the new Vega APUs.
But this time they're actually making a play for the discrete graphics market. They've hired Raja Koduri and everything. Not the first time they've done that either (see: Larrabee) but they do look to be making a serious attempt.
They're not in the same performance class. A Crystalwell Iris Pro 580 (and the 2500U) are slightly slower than a GTX 750 non-Ti. The new Intel APU is going to be ballpark RX 570 performance - or something like a 1060 3 GB on the NVIDIA side. About 4x the performance - which is absolutely necessary for the sorts of applications Hades Canyon is aimed at, like VR.
Having a discrete graphics die, and especially having access to HBM2, makes a huge difference in performance. There isn't much you can do with 30 GB/s of bandwidth to share between CPU and GPU. Having Crystal Well L4 cache is a huge boost but it's still a halfassed fix compared to having proper VRAM available.
Of course, it's also a vastly more expensive part as well. Just the CPU+GPU package is more expensive than some of the 2500U laptops.
Presumably Intel is aiming for something more like Vega M GH with Jupiter Sound/Arctic Sound - it makes little sense to design a low-end discrete part with no room for future performance growth.
