Because AMD and Nvidia don‘t have their on Fabs.

But they would build them with that money. That's what it's for.

No, they wouldn't. That wouldn't even build them one fab, let alone summon all of the talent and supply chain out of thin air.

I’m not convinced either of them would even want to.

AMD used to have fabs - they spun them off a long time ago as GlobalFoundries. They’re no longer competitive with TSMC, Samsung, or even Intel for modern nodes.

Lol? No, wtf

Also 8bn is like 1/3 of modern fab