I post instruction several days ago
Step 1 : boot into recovery and from terminal there issue the following
csrutil disable
csrutil authenticated-root disable
Reboot
Step 2 : once back at desktop, from terminal type mount, you should see deviceses like /dev/disk1s5s1, your case might be different, or whatever your name.
Step 3: from terminal type mkdir mnt, it will create directory in your user home
Step 4: mount this as following:
sudo mount -o nobrowse -t apfs /dev/disk1s5 mnt/
make sure you use disk1s5, not disk1s5s1, remove last "s1"
once mounted from terminal
sudo rm -rf mnt and drag application you want to delete, for example
sudo rm -rf mnt/System/Applications/Maps.app , hit enter
repeat for any application you want to remove
Step4: once done , you need to bless the folder
from terminal
sudo bless --folder mnt/System/Library/CoreServices --bootefi --create-snapshot && sudo reboot
once reboot your application is gone forever.
P.S
in Mojave it was easy, in Catalina it was relativly easy , you still can mount volume by ussing "sudo mount -uw/"
BUT Big Sur, uses snapshot, so you cannot mount it the way in Catalina, and once you done messing your system, you need to create new snapshot, by using "blessing" comand.