It uses low-power components (U rather than H CPUs for example) and isn't capable of generating nearly as much heat, regardless of what you're asking it to do.

Switching from a core H to core U will cut your perf in half. I like my xps 13 but in all fairness it struggles to run Firefox with youtube+gmail+slack and Office open all at the same time. As someone who primarily uses beefy desktops, it feels about as snappy as a Core 2 Duo machines with DDR-400.