IMO, laptops just aren't great gaming machines. in a gaming PC, we have liquid cooling, lots of fans, great airflow, and you push the limits.

On a laptop, they try their best to get the most performance, but you physically don't have the ability to have the same cooling. There is no space to allow nice airflow and cooling. Additionally, it drains the shit out of the battery. With gaming though, most of the lifting is done by the GPU, which is why I think the future of laptop gaming will be an external GPU via TB3, that can be powered separately, and cooled away from the rest of the laptop. This will allow for thinner, more portable laptops, and when you want to sit down and game wherever you are, just plug in that GPU for better performance.

My personal experience has always been with Sager computers (for power computing), and I always ran into the same problems. Overheating, constantly needing to clean out the fans, and a massive drain on the battery. I think I need to change out the thermal paste on my GPU as well right now on my last one.