For many companies (country-dependent) that's not really why they use cloud services vs purchasing. It's tax shenanigans and business process overhead. OpEx vs CapEx, and a small (%) bump in the huge AWS bill no one will even notice or a $30k+ invoice for hardware that has to go through rigorous review and 3 departments.

Same reason people pay for things through the AWS marketplace (like Vanta) instead of having to go through their invoicing process.

Good point. Maybe there'll be companies that maintain your on-premise GPU cluster just like there are companies that service the coffee machine in your office?