Hi Nik,
I'm Amr, an independent advisor.
There is no clear explanation from Microsoft until now why natural voices are only available for the Narrator and not for Text to Speech.
However, there are some third-party solutions that can provide natural voices for Text to Speech in Windows 11.
One such solution is the Acapela TTS Voices app, which offers a range of natural-sounding voices that can be used with various Text to Speech programs.
Another option is to use a screen reader software that supports both Narrator and Text to Speech, such as NVDA or JAWS, which may offer more natural-sounding voices.
You can always provide feedback via the Feedback hup app so Microsoft can hear your requests and act accordingly, that because we are not Microsoft employees we are independent advisors trying to help with common issues
https://support.microsoft.com/en-us/windows/sen...
I hope this is helpful. If you require any additional assistance, don't hesitate to respond to this.
This is a user-to-user support forum. We're users just like you helping other users to find solutions to their problems.
Best Regard
Amr