I write CRUD apps that run on industrial machinery. Do I need to support screen readers? Many of these machines require very good vision to operate. It's just not safe if you can't see what is going on.
Nah, an industrial machinery interface won't be liable for ADA suits. Title II of the ADA only covers "the benefits of the services, programs, or activities of a public entity"[0] – public being the keyword.
You are legally allowed to make an accessibility hellscape of an intranet site :)
Many of these systems are an accessibility hellscape for users with 20/20 vision. They're bult expressly to the desires of upper management without any input of the people operating the software.