Not sure. So far, I found every text to speech application quite uncanny. The ones that come with Windows, MacOS, Android, iOS are good, but not quite there. The TikTok one is the first to sound quite convincing for me.

Siri and Alexa are also good but I think they don't count, because they probably are not purely text to speech but presumably use a lot of prerecorded phrases, especially for the common answers.