I’m still missing what the problem is. I can remove all of those apps right now and set other defaults. I currently use ProtonMail as my default email client and don’t have Mail installed. I can use any messaging app and use signal almost exclusively. Apple’s Messages can be removed. Apple’s Maps can be removed.
Kind of...
Mail and Browser can be set. Mail doesn't always work 100% - I also use ProtonMail.
None of the other default Apple apps can be set. Only these two.
We need more that can be set.