USB C to AUX adapters work for me.

Having a secure and up to date device should likely be more important

Yes. Many security updates come from upstream AOSP and then are put into GOS.

So when a device has stopped getting AOSP updates, it is unreasonable for GOS to continue support it. They can and I believe they have applied more critical security patches to just barely EOL devices, but this isn’t promised or expected.

https://endoflife.date/pixel This is for googles support. GOS may support a specific device a little longer than google but does not promise to and recomends getting a newer device.

Pixel 8a looks real good right now.