The examples you cite are exceptions, not the rule.
Most Google engineers still work in CA, and it's easier to get hired for a role at HQ because there are always openings for all kinds of positions. For the smaller offices, they might only be hiring infra or only hiring L6+, etc.
For movies, think about what you'd do as a young actor trying to get a major role. Would you live in Atlanta where a handful of films are shot every year, or would you live in LA where hundreds of opportunities come up every month?
This isn't true. I've known Googlers who worked in Ann Arbor, Pittsburgh and NYC. I've enjoyed many films made in Georgia. Places like NM, Georgia, Austin, etc. are enticing filming there because they know the industry can support more than just one hub in LA. Now filmmakers know they can work and play in Atlanta, Albuquerque or Austin, places cheaper than Hollywood. Places where you don't need family assistance for a down payment on a house. A Googler could do the same in Pittsburgh.
I think it seems very wrong that the dichotomy of career vs home-ownership is as harsh as it is
Is it? OK, I'll grant that it is if you have a singular mindset of "I must own a home right now and I can only have a fulfilling career bay area", but you aren't entitled to live and work in a specific place. And who cares? There's so much more to this world than that.