yeah real programmers only use the biggest screens, the bestest cpus, and discrete graphics

"bestest" CPU is not required, but with 13 inch screen you have to either make everything tiny and strain your eyes, or have only 10-15 lines of code in the screen. Also, modern websites and apps use gigantic font size and you will have like 3 paragraphs of text in one screen.

Companies have standardized on, mostly, 13” laptops with whatever accessories. But, honestly, for some people who never leave their desk, a desktop of some sort is probably a better choice— though just connecting to a server works too.