I made some adjustments to my image recipe, such as using dnf instead of rpm-ostree, removing and adding some packages and enabling the negativa17 repo, but nothing, beyond that, that would cause boot problems. I'm suspicious of an option that is this:
install: install-weak-deps: false # Whether to install weak/recommended dependencies.
install: install-weak-deps: false # Whether to install weak/recommended dependencies.
Here is my repo for anyone who wants to investigate the commits and files: