I know the Zoom app has some wonderful features to accommodate a variety of disabilities. Unfortunately, I don't think voice recognition is a thing during a phone call access to a Zoom meeting. But sounds like a great "feature request"!
Please consider making a feature request here at this "feedback" link:
Us volunteers here in the Zoom Community don't have a way to document your request, but the Zoom Staff will log any request filed to be considered by Zoom's engineering team.
Thanks for that suggestion. I did suggest that as a new idea for the multitude of senior citizens with limited vision and disabilities, as well as many other folks who would make use of zoom, if they only could.