General purpose laptops are made for the general purpose end-user.
That person is using Office, Surfing the Internet, Facebook, YouTube, etc. Nothing demanding (performance wise)
They're more concerned with extended battery life than the laptop sustaining maximum uninterrupted thru-put.
We (as DAW users) are on the opposite end of the spectrum.
We need maximum sustained (uninterrupted) data thru-put.
Low/consistent DPC Latency is necessary to effectively work (with substantial loads) at low audio latency.
With an off-the-shelf computer, many advanced BIOS parameters are hidden from (not exposed to) the end-user.
This reduces the load on tech-support (ensuring folks don't foul up their machine), but it comes at the expense of not exposing some parameters that help minimize DPC Latency.
DPC Latency isn't a factor for the general-purpose end-user. They would never notice a 3ms hiccup in data flow.
For DAW applications (especially when working at low-latency settings), a 3ms hiccup in data flow results in glitches/drop-outs.
A laptop is a super tight space. The ultimate small form-factor.
To keep temperatures in check, performance compromises *HAVE* to be made.
Notice that the clock-speed of laptop CPUs hasn't changed much in a long while.
2.4GHz is relatively slow considering desktop CPUs are now running quad-core CPUs at 4GHz
I've said this many times, but I'm just not a fan of laptops.
I'd rather have a mini-ITX machine (still very portable) that has all the speed of a tower and none of the limitations of a laptop.