Why is the Torah still hand-copied today the same way it was in ancient times?
There are very many reasons, but the reason that comes before all the other reasons is because G-d commanded it to be so. “V’atah kisvu lachem…” You shall write it for yourselves. This is a commandment to continue writing the Torah scrolls precisely as they were first written in the desert between Sinai and Israel, 3,319 years ago.
No lengthy document in the world has been so perfectly preserved through thousands of years as the Torah, and this is a big part of the reason why.
Regards, Eliahu Levenson