Even if they could make a fab, it would still be a logistical nightmare to scale from 1-1,000 users. Meanwhile, my SaaS company could have 100,000 users thanks to the cloud, and I wouldn't even have to get up from my desk.
Non-sequitor [1]. AMD not having a fab doesn't mean a EE can run a fab out of their garage.
It may be relatively easier for people to make new chips without needing AMD/Intel (see all of fang company making their own). But it's still companies with lots of money making new chips and not people in their garage.