Well, it would indeed be horrible if people can't write in their own.... letters.Â
I write, e-mail, text, and chat all the time. Even all at once.
One time I wanted to buy a calligraphy pen for my MAPEH class (Music, Arts, PE, and health) and a saleswoman told me that they don't sell those anymore. For the reason that no one uses it anymore.
But even though more and more people would find e-mailing a lot more convenient, there would still be those people who would find writing by hand more convenient. It's like a flow. So old writings won't die completely.Â
Chances are, people might quit e-mailing and sorts in the future because of "Health risks"