Why does Airbnb need a "tech hub?"
I think going through this exercise will show it's more than "just a website"
Airbnb is investing in their business, in what they believe (and they probably know from their numbers) will grow their future. They don't have to rationalize it only if there is complexity involved.
To agree on different grounds;
They had some remote employees before; have had some remote employees (awkwardly, as an exception while promoting remote work), and will have been all remote for 1.5 years by August.
Will this actually hire jobs in the area? Or is it going to be a reserve office for occasional team building events that is located near a major airport.