AngularJS is not for websites

This does not seem to have anything to do with Angular at all.

This looks like the typical case of the website that was shipped out the door as soon as possible without any accessibility concerns, that have to be shoehorned afterwards.

This would have happened independently of the technology used to build the site.

Angular added native support to the ARIA attributes in version 1.3 https://docs.angularjs.org/api/ngAria