What many people don't get is that "custodial vs. non-custodial" is NOT about how secure the Bitcoin is that's held by the custodian. It doesn't matter. Think like an autist or a mathematician:

Do you control your Bitcoin, yes or no?

It's not about "how easy can someone collude to steal your Bitcoin that you don't control" or "does the code run in an HSM" or "theft would be detectable". All these things don't matter for this question. They're interesting but that's not the point. You're thinking about the wrong categories, namely *security*, not *custody*.

Words have meaning. Unilateral exit is a necessary condition.