For what it is worth, it appeared to me that my Speech settings in Accessibility Preference Pane were corrupted somehow. If I played any voice in Speech section of Accessibility Preference Pane, my System Preferences application would hang.
I ran this command in the terminal
tccutil reset Accessibility and restarted the computer.
Speech module started working.
I had to reenable permissions to applications that required Accessibility access under Preference Pane - Security & Privacy - Accessibility.
Hope this helps anyone else who has this problem. I am no expert so perhaps others can chime in on the underlying details as to why
tccutil reset Accessibility worked to address my speech preference pane.