how crucial ARIA support should be ?

[emchateau]

Various web components libraries are centred around accessibility. Cf. React aria, etc. Accessibility should be a high priority for the project. Instead of seeing it as complexity, that should be embrasse broadly as a way to enhance functionality and linked to the responsive aspect of the components.

[emchateau]

The accessibility issue is really important in my point of view. So we need to get this into the development pipeline as soon as possible. If not immediately.
The question of accessibility is now a prerequisite for all content produced in a government context in France and Canada. The requirements of Digital Museums of Canada are very high.
We have expertise on these issues at the Université de Montréal that could be mobilized (at the School of Optometry and at HEC). CRIHN colleagues working in translation also include accessibility in the scope of their work.
It's not just a question of ARIA. There are many standards and best practices involved. Cf. Ouvroir bibliography.