The element object is accessible in the elements/_element.plate theme file, if it’s rendered by the {% render_content %} tag inside the {% content_for column %} block. Read more on how content_for works here.
The elements/_element.plate usually calls the {% content_for element %} block, which renders the :plural_element_type_name/_singular_element_type.plate theme file, with access to the same element object. However, in this case calling the singular content type name returns the element object.
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element.content_type
Returns content_type object.