Willie:
I'm not sure this is a really important regression. You can configure the new GDM to always launch various AT programs as needed. The main lost feature is that users cannot launch AT programs on demand.I'm curious who the "you" is "you can configure." The important thing here is independence. People with disabilities need to be able to do as much as possible without the need for assistance.
Since GDM has never had a11y turned on by default, a person with disabilities would likely need help to set up either the old or new GDM to work for them. Or, if a person could boot up into console mode with a11y enabled, then the person could probably set up the configuration themselves. The long-term goal is to make GDM and GNOME in general work better for independent usage, but we're not there yet. Brian