I have a Raspberry Pi 4 with the bookworm version of Raspbian, and the Mic+ V2 installer script reports an unsupported version of Raspbian. Is there a more recent installer script that will work?
Thanks for reporting it, we have updated it please try again 
wget -O - mic.raspiaudio.com | bash
The script prints this line:
Adding Device Tree Entry to /boot/config.txt
However, if I look at that file, the contents are:
pi@raspberrypi:~ $ cat /boot/config.txt
DO NOT EDIT THIS FILE
The file you are looking for has moved to /boot/firmware/config.txt
dtoverlay=googlevoicehat-soundcard
pi@raspberrypi:~ $
I’m not sure to understand is it working for you? if not please share the full logs