https://github.com/plone/plone.dexterity/blob/master/plone/dexterity/browser/configure.zcml
The default view for Dexterity content uses a WidgetsView and renders all widgets in display mode.
The standard view definition in browser/configure.zcml references the page template involved:
<browser:page
for="..interfaces.IDexterityContent"
name="view"
class=".view.DefaultView"
template="item.pt"
permission="zope2.View"
/>
Additionally, the plone.app.dexterity package overwrites the default view for containerish content types with:
<browser:page
for="plone.dexterity.interfaces.IDexterityContainer"
name="view"
class="plone.dexterity.browser.view.DefaultView"
template="container.pt"
permission="zope2.View"
/>