got it working!!!
dracut /boot/initramfs-6.8.7-300.fc40.x86_64.img 6.8.7-300.fc40.x86_64
Found on this page:
https://superuser.com/questions/1684…684790#1684790
Was using dracut slightly wrong for the purpose of getting initramfs in the root of the boot partition before, but now all is good.
Still doesn’t explain why the updater didn’t generate a new initramfs during the dnf upgrade process.