I worked with two blind systems people for close to 5 years - we were all working remote, so initially I had no idea they were blind - and subsequently learned from them about their struggles and frustrations dealing with shitty or nonexistent accessibility features.
And with assistive devices’ drivers that were broken, or not updated since Windows State of the Ark version, or not available on Linux or Mac, and so on.
These two people dramatically improved the accessibility features of the smartphone product that the company sells, by reporting the issues they found while dogfooding it. They raised the awareness of many people, including me, of the challenges of the blind, particularly in technology settings.
As a result, I learned ‘dot’ (graphviz) pretty well, and became much more text-centric in other ways (e.g. using markdown, avoiding images when possible, adding alt text).
Slack has done the community a disservice by dropping support for open protocols like IRC and XMPP, which support text-based interfaces that work well with screen readers.
So screen-reader usability is still a thing. The fact it's not using a proper standard open protocol is a problem.