^ Desktop Skylake i3's and above are fairly close to AMD's iGPUs, on average, from what I've seen. There are still cases where AMD pulls ahead significantly, most likely because Intel doesn't spend nearly as much time optimizing for specific games. If Skylake's iGPU is "mediocre", then so is AMD's... and I'd probably argue that, yes, they're both mediocre.
If comparing a Celeron/Pentium without a discrete GPU vs an A6 or A8, then yes, I'd say the AMD CPUs will have a broader range of usefulness. There are plenty of games where AMD APUs simply cannot provide a playable framerate at all, regardless of settings, but the number of games will be smaller than those chips equipped with, say, Intel's 510 iGPU.