L&LD
Part of the Furniture
but not all other components on the bord!
It is not a PC mainboard where CPU get cooled by a fan and surround components keep quite cool.
Here the heat is spreading throughout the wholecircuit board inside housing.
I'm sure the millions of Asus routers sold over the years attest to their designers' decisions.
Sure, a few may be marginal and fail, but I haven't seen one yet that has died from overheating.
And I agree; this is not a PC mainboard. It is simply a router.