remote_user used with a loop results in fatal "item is undefined" about ansible HOT 4 CLOSED

vars:
  ansible_user: “{{ item.user }}”

# assume I have created a list of {user: some_user, host: some_host} dicts
- name: "use inventory to get mirror hosts"
  ansible.builtin.add_host:
    ansible_ssh_host: "{{ item.host }}"
    ansible_ssh_user: "{{ item.user }}"
    inventory_hostname: "{{ item.host }}"
    groups: "mirror_hosts"
    name: "{{ item.host }}"
  loop:
    "{{ mirror_config }}"

# run_once is called because this is a task in a playbook using N hosts
- name: "do something with group"
  ansible.builtin.file:
    path: "/home/{{ ansible_ssh_user }}/touchfile.txt"
    state: "touch"
    mode: "0644"
  loop:
    "{{ groups['mirror_hosts'] }}"
  run_once: true
  delegate_to: "{{ item }}"