It's worth noting that there have been occasions where the library was blocked and it took a few weeks to workaround said block. For example, when a valid Sec-MS-Token became required, it took a while to implement it in the library: https://github.com/rany2/edge-tts/blob/08b10b931db3f788a506c...
Basically, it's a very bad idea to use this library for anything serious/mission critical. It also is really limited to only taking in text (i.e., no custom SSML, emotion elements, etc) as Microsoft restricts the API to only the features Microsoft Edge itself already supports. Generally commercial users would want these more advanced features and so they'd want to use Azure Cognitive Services.
At any rate this library was never really marketed, I'm not sure how it blew up. It was really only intended so that I can have audio files I can play back for my Home Assistant instance. Later, I started using it to generate e-books. In general, these are the two main uses of the library AFAIK.
While technically the library could continue supporting custom SSML, I ended up removing it because keeping the support was pointless. The API stopped allowing anything other than the basic tags used by Microsoft Edge itself (i.e., prosody for rate/volume/pitch, voice, etc).
As for comparable projects, you can use Azure's offerings instead. They have a free tier that's really generous.
Basically, it's a very bad idea to use this library for anything serious/mission critical. It also is really limited to only taking in text (i.e., no custom SSML, emotion elements, etc) as Microsoft restricts the API to only the features Microsoft Edge itself already supports. Generally commercial users would want these more advanced features and so they'd want to use Azure Cognitive Services.
At any rate this library was never really marketed, I'm not sure how it blew up. It was really only intended so that I can have audio files I can play back for my Home Assistant instance. Later, I started using it to generate e-books. In general, these are the two main uses of the library AFAIK.