Canon R5

Hold down the Option key and go to the  menu and select System Information. Then in the sidebar go down to Raw Support under Software and see if the Canon R5 is listed.

This is what I found with Ventura:

It looks like it's supported in Ventura so it would be in Sonoma.

But you have to be careful with this, since sometimes it does not actually download support until you need it.

It shows up in the Ventura list:

Digital camera RAW formats supported by iOS 16, iPadOS 16, and macOS Ventura - Apple Support

So it will be there for Sonoma, too.

I added Sonoma to my google search and found this:

Digital camera RAW formats supported by iOS 17, iPadOS 17, and macOS Sonoma - Apple Support

You are covered. In fact it looks like all the Canon R's are supported.