You are right when speaking about thin and light laptops.
I have been using already for many years a Dell Precision 15" mobile workstation laptop, which does not have any overheating issues.
In steady state, i.e. for an indefinite time, its Xeon CPU can dissipate 60 W without overheating and with an only audible, but not annoying, fan noise (the CPU is configured for a 60 W power limit, even if its nominal TDP is 45 W). The NVIDIA Quadro GPU must be able to dissipate simultaneously more than the CPU, perhaps 75 W or 90 W, but I do not know how the GPU power limit has been configured.
This laptop is rather thick and heavy, but not enough to bother me when carrying it in a backpack, and it has perfect Linux support. I do not know if the current Dell Precision mobile workstations have retained a so good quality as mine (which is the 2016 top 15" model).
While a thick and heavy laptop can provide good cooling, such mobile workstations or gaming laptops are quite overpriced. For a computer that must be carried in a backpack or briefcase, but which is intended to be used only plugged in the mains electricity supply, it is possible to achieve better cooling, higher performance, a much lower price and also a noticeably lower total weight by replacing a big laptop with a portable monitor, e.g. a 17" one, a compact keyboard and a SFF computer, e.g. a NUC-like computer with a volume between 0.5 L and 1.0 L.