zals only depends on ansible-core in the part that runs ansible-playbook --syntax-check. And the only reason to do that is to provide the same functionality that official ansible VSCode plugin provides. So if you do not need playbook syntax check, you do not need ansible-core at all.
Same with ansible-lint - only used because official extension uses it.
I am planning to create something similar to ansible-static-lint Release Announcement: ansible-static-lint v0.7.0 hopefully more extendable, I want people and agents writing their own lint rules.
Ansible-static-lint is also good project and deserve some attention.