As is the conclusion of the article, one of the easiest things to do is simply raise the laptop more off the surface so there's less impediment to airflow.

https://www.amazon.com/Computer-Keyboard-Anti-Slip-Compatibl...

I was recommended these by a friend and the ability to easily do that anywhere (and as a nice side-effect get a lovely angle to the keyboard) but still be able to pop the laptop in a backpack easily is amazing. They have been put on every laptop my wife and I have owned for the last 6 years.