I'll chuck in another rationalisation from just one angle (of many). It's a low in demand feature that if they implement they would have to support. One thing that Apple does incredibly well (I really can't think of any tech company that comes close) is provide front line support for virtually every capability and feature in the Apple ecosystem. This means they have to resource support people to know how the feature works, and troubleshoot it when things have issue, dedicate engineer resources if an issue cannot be fixed and requires escalation, etc.

Just having such a feature involves a cost, and the juice is just not worth the squeeze.

Curious, if your phone supports the feature and it doesn't work, what is your recourse?