You can see here, that the same is true for HorizontalStack, there is no export available for VerticalStack:
HorizontalStack:
When I click VerticalStack in the Build an App tutorial documentation, it takes me to BlockStack documentation.
When I click HorizontalStack on in the Build an App tutorial documentation, it takes me to InlineStack documentation.
Where did HorizontalStack and VerticalStack go and how can I find out about big changes like this?