It is not true that they do have hardly any impact on accessibility. But if you want to go that way: MVP.css uses `<label>` instead of `<fieldset>`/`<legend>`. See https://www.w3.org/TR/WCAG20-TECHS/H71.html.
Nah they don't. I've had accessibility tests done and checks by Foundations for government. Even they don't care about it, it's all about: contrast, letter size, tabs and titles/labels.
I'm not sure why you are so insistent. Of course it is important for accessibility. I have also worked for government sites, conducted a11y tests myself, and worked with independent auditors from Canada and Germany. Semantic HTML is a very basic but critical part. See https://www.w3.org/WAI/WCAG21/Understanding/info-and-relatio....
