MacOS accessibility system voice has a gag order against Siri

For a while I wasn’t able to get the new-and-improved version of Siri’s voice (“Nora”) on my older Macbook Pro, but after troubleshooting I got it going. The problem now is it just won’t trigger for anything, even when it’s set as the default for reading text aloud. I get good ol’ 16-bit Alex or Fred when I want Siri Female. She’s set as the system voice but whenever I tell Kindle or Adobe Reader to start reading a page to me, one of the old male voices starts yammering. Any ideas?

EDIT: Apparently it’s a known issue/expected behavior. See: