Laptops almost always have cooling which definitely won't sustain 100% CPU or GPU usage for 2 hours for a buildjob. On my desktop with fairly standard, non-fancy air cooling, I could run it on 100% for hours, and the only thing which would happen is the fans spinning loudly. On my work laptop, the poor thing (with an i9!) begins to heat up like crazy after 5-10 minutes of virtual machine usage.
I have noticed here on HN that a lot of people don't have desktops and think they are as good as laptops in terms of performance. lol