You want replies to open with the customer's name without typing it or maintaining a template per customer.
Templates support variables that resolve at expansion time. The recipient variables, {{to.first_name}} and {{to.name}}, are filled from the message context in Gmail, Outlook, and LinkedIn messages. On sites without an adapter, including Zendesk and Gorgias for now, they degrade to fill-in fields: the text expands and you type the name yourself. That fallback is deliberate, so the template never guesses a name.
Write the template once with a placeholder such as Hi {{to.first_name}},. Use it in Gmail or Outlook and the name arrives filled in. On Zendesk or Gorgias, fill in the name fields after expansion.