Most laptops don't use a completely custom SoC, but most of them have enthusiast driven driver support -- or worse, formerly-enthusiast driven driver support where nobody currently cares -- with no support from the manufacturer. And on less popular hardware; the most popular laptop models in the world are macs.
If you want manufacturer support, you need to use macOS or Windows or one of the very limited selection of laptops which feature Linux as an option. Most people who use Linux probably already use Linux on a computer without manufacturer support. If that's not for you though, that's totally fine.
