Thanks for asking question! Azure Communications Service doesn't support Simulcast. Also, The best way to share your feedback would be to create a User Voice feedback item and upvote it. The product group monitors this site for feedback. This is the best way to ensure you are heard and you may receive a response depending on how much they information they can currently share.
Azure Communication Service documentation link: https://learn.microsoft.com/en-us/azure/communication-services/
Hope this helps. Please Let us know if further query on this.