There is a minimum intrusiveness required by law, though. One could even say it's intrusive by design, depending on your perspective

OP said after 2008. There are many cars made after 2008 that do not have intrusive systems. For example, my 2018 Camaro has none of that. The only proximity sensors it has are side vehicle indicators and all they do is turn on a light.

New cars with intrusive driver monitoring alerts are obviously going to be terrible but you can still buy vehicles made prior to this change.