Most of these companies are there because of the HP campus set up there in the 70s/80s. HP liked setting up offices in small towns near colleges where they were the essentially the only tech employer. Broadcom bought HP's fab facilities after they divested. Microsoft started an office there because they wanted to hire optical mice engineers who were working for HP.

Source: Used to work at the Microsoft office in Fort Collins (HoloLens group). Some of the folks I worked with were the original folks that set up the office.

It's sadly been moving a bit the other way. HP/HPE have significantly downsized and Microsoft's office is pretty tiny. I"m not sure AMD even has an office here anymore, if so, they took down the sign on the building it used to be on.

HP, Broadcom, Intel, and AMD used to all be on the same intersection.

And Intel just chopped the size of the office in half. They don't use the upper floor anymore.

People who have been to Fort Collins know that that city needs a _lot_ of infrastructure work to become anything more than it is now. FC already bulges under the pressure of college move-in/out and tourism there is fairly big for Coloradans. I also don't think residents are the kinds that would go for large expansion. Denver still has more than enough room to grow before they push out into the smaller towns, and if they did Boulder would go first since it already has a startup ecosystem IMO.

Do not underestimate the impact of a very large airport on the decision making of senior execs.