I have created a few email templates using the new email template builder. I can see that the emails are sitting in the public email templates folder.
When I click Email Content, then click Email Templates, none of my templates are able for selection. It seems like it's a folder permissions issue, but they reside in a public folder?
I found the resolution... Salesforce gives you the option to upload files using the new lightning builder. However, to use Email content and select from available templates...all media/content has to come from CMS content. You CAN NOT use Salesforce files or the template will never show for you to select from under Email Content.
All makes sense once you find the answer.
For the Email templates to be visible in the Email content object >> 'Made in Email Template Builder' should be checked and 'Contains Salesforce Files' should be unchecked. Any mismatch to these values then these email templates will not be visible.