Set Mail Read Delay - Will this ever return??

When using the mail app with the preview pane open, even scrolling past a message in the message list will immediately mark it as read. There used to be a setting (years ago), which would allow the "mark read" delay to be set to something non-zero. 5-seconds is a usable number, for example.

This capability, along with plug-ins that would allow this capability, was removed with Sonoma and beyond. Why? This is the ONLY feature preventing me from using Apple mail.

Will this capability EVER be added back in? Many, many, many people have asked for it. If not, why not? It is a serious impediment to using Apple mail for heavy email use. Others suggest using the 5-line message preview, but that cuts the number of message in the list on-screen that can be seen. Every other email client I have tried allows this feature.

What is the justification for REMOVING it? What am I missing?