Re: Just make such tools illegal too.
The option of "just don't have the technology" is always considered, suggested, superficially functional, and impossible. The same way that "don't have an internet" didn't work when the first abuses were known. The same way that, when there were ten computers in the world and people's ideas of what they could do came from science fiction stories, fear of them did not mean that we just decided to ban them and keep going with manual methods. You can try to ban developing the technology, but it won't stop people, especially as multiple open source versions already exist. They have valid uses, and anyone making one will say they're intending those, whether they actually are or not. If you ban it in one country, it will just be developed in another one.
You can only try to ban a technology when it is prohibitively difficult to develop it, and even that doesn't always work as demonstrated by the number of countries that have or could develop nuclear weapons. Those take a lot of money and things that are hard to just buy, and yet programs to do so have succeeded. Someone can build a voice cloning tool on a home computer, even though it won't be as good as an organized corporate effort. You won't be able to do very much to prevent that.