Though depending on your situation a laptop will do both, think the thing you’re missing is that you can plug a laptop into a monitor mouse and keyboard the same way you do a PC and it will be functionally identical, except you have the option to unplug it and take it with you if you need to
Personally I have a gaming PC at home and a laptop for work, and a USB c hub that lets me plug said laptop in and use it as a desktop if needed. Perfect setup imo