Welcome to the community, @David_Pratten!
Airtable has a lot of weird quirks. One of them is that it doesn’t respect default values if the new records are created through anything but the Airtable data entry interface itself.
If you create the new record through a form or through the API, the default values won’t appear. You can email support@airtable.com to request this as a product suggestion.
In the meantime, the workaround would be to use automations to assign values to any new records.
