Ask HN: Desktop or Laptop with eGPU

I currently have a MacBook Pro, but I'm also thinking to get a Windows machine. My options are to either build a desktop or buy a laptop and a eGPU (probably Razer Core X). The benefit of the desktop is upgradability and performace; however it is not portable. If I get a laptop (probbably a ThinkPad) and an eGPU (with Radeon VII), i can also use the eGPU with my MacBook Pro. What would you reccomend?