Laptops aren't made for gaming anyway. They can, but they're big workstations. It's their main purpose.
Upgrading a laptop is possible. You just have to find the right parts but it usually means going back to the manufacturer of your laptop, ordering pieces,etc. A bigger headache then it needs to be.
I'd buy a laptop if I needed a mobile workstation(if you travel a lot and your job requires you to use one).