That is quite hostile to their consumers, no matter how they spin it. If you put a budget on something it should be capped.
I think I read somewhere that calculating and limiting cloud usage costs is a really hard problem. But I feel that if Google were motivated to do it, they can do it. It's hard, not impossible. They just don't care to solve this particular problem.
Why doesn’t GCP provide a way to say “shut down all my services if my cap is reached”?