A top-spec MacBook Pro is >$4k, so I assure you that plenty of computer people do own $4k of computer hardware.
Hell, most tech folks are wandering around with a ~$1k smartphone in their pocket too.
A car is super useful, so is an AI. But even if we decide cars are incomparably more useful a great many people pay much more than $4000 over the minimum viable car, and that's money that could be deployed to secure access to private, secure, and autonomous AI facilities. A few thousand dollars in computing is consumer hardware, or at least could easily be with more reason and awareness driving adoption.
People spend a LOT of money in things less useful than local copy of qwen3.6-27b can be.