It’s not that hard to comprehend both measurement systems. Both are valid and it’s up to the author to choose how they want to express their figures. You can send them a complaint if you want, but complaining about their measurements here isn’t going to change anything.

I hear tell them cameras is full of valuable minerals like gold and copper!

Everything in this post is wrong, actually. But if you buy shit parts to build your desktop, you’ll have a shitty desktop.

Simple answer is at the motherboard level - you look at your motherboard’s future expansion capability and if you started with a good foundation you can do years of upgrades. Also your computer case needs to be big enough to fit extra stuff, full ATX motherboard size is great.

For example I have a VR gaming rig that runs VR games well on DDR3 RAM and a Sandy Bridge CPU, because it has a decent modern GPU and enough CPU cores + RAM.