How does Dagger help? I just can't get anything concrete from their site.
If you’re working on a team often your shell scripts, python programs, and makes files are not always portable between local and CI, but even worse between your local machine and your colleagues local machine. This is where dagger shines because it lets you do all that stuff in a fully portable way.
Low pro teams and individuals will happily abuse any new tool.
Mature teams stick to local-first CI - i.e. be able to run pipeline locally - and then translate to whatever is being used in their build and test infrastructure.