OpenAI doesn’t take feedback articulated clearly, and removed the obviously useful monthly budget hard limit that used to exist for projects and replaced it with illusion.
One can only think that they deliberately enjoy additional profit from overages, abuse, and lack of management interface, just as they enjoy expiring your credits.
You can use a daemon loop of monitoring the admin endpoint usage by daily buckets for a project, and then have hooks to delete all the API keys for unusual use - as long as that also stays working.