Do accessible user agents mean that authors no longer need to produce accessible Web content?
No. Authors of Web content, and developers of Web software, have complementary roles. For instance, to meet the needs of some users with visual disabilities, authors must provide a text description of an image; browsers cannot invent a meaningful description of an image. Once an author has provided a description, browsers, together with assistive technologies, can present the description as either synthesized speech or braille. See also the question on the relation of UAAG 1.0 to other WAI accessibility guidelines.
