Hiding notifications for Filtered Unknown Callers

Yes, at time, you still get banner or badge notifications, depending on what you've selected for the "Phone" app.

No one here in this user-to-user forum would know Apple's plans for the future. However, you can let them know what you'd like to see here:

Product Feedback - Apple

I'd recomend using the iPhone option as I don't think there's anything specific for the "Phone" app.

I agree with you that this should be an option.

Hello,

Go to Settings>Phone the school down tap Silence Unknown Callers And turn the feature on,

I recommend this-

Detect and block spam phone calls - Apple Support