Concerns with ARIA only indicators for structural elements

With more people embracing the use of ARIA, I am concerned that reliance on
ARIA only to convey structure will be a problem.



For example, the ARIA role of heading can be used with the level attribute
to specify headings on any element.  When a page is viewed without style
sheets or with a custom style sheet all heading levels would likely appear
the same – without a change of size that you would normally get from using
HTML heading structural elements h1, h2, h3, etc..



I believe this could violate WCAG 2 SC 1.3.1 Information and Relationships
as there is no differentiation of headings unless a custom style sheet with
CSS for the heading and level roles was implemented.



Do people see this as a user agent issue or a WCAG 2 violation?



Jonathan