There are a lot of things to comment on this post, but in general I just think things are being looked at from the wrong perspective.

A small fraction of WP users wants to add a shop to their site - so WP doesn't come with WooCommerce preinstalled. Few users want to create custom user roles, so there are addon plugins that offer the ability to create them.

But then suddenly not every WP user needs accessibility aids, and still that must be in core. Even worse, it is being pushed on to 3rd party developers to adopt them in their own products.

In my opinion, WP core should only have the features that will be needed/used by a large enough fraction of its users. Everything else should be left to extensions (themes and plugins). And under no circumstance should the WP team impose any obligation on these extension developers to include the demands of more users. Especially since this only happens very selectively.

A lot of the text is about creating empathy with those who need the aids. I can only understand that the author believes that those who do not support accessibility aids in every theme have no empathy for those who need them.

I can't speak for everyone else, but that is certainly not my case. It must be awful to have any kind of impairment, and I really hope people who do can find aids in and out of WP that will make their lives easier.

But I believe the motto should change from "It's okay to be different" (which is correct in itself, it's just misplaced) to "It's okay to add plugins to make your WP more what you need."