Well idk about you, but throughout my education I filled up a lot of notebooks with notes and assignments, and I took plenty of written tests.

There are numerous studies showing that writing by hand improves memory retention and speeds up learning.

There's a superior system of writing by hand that allows you to write faster, have less hand strain, and end up with something that's easier for everyone to read.

Try to connect the dots.

As for how it's useful to you today?

Why do we need PE when the purpose of physical development is to be able to move in space? The vast majority of movement today is done by man made vehicles. Basically the only time you have to move by using your legs is when you're going to the car or the toilet, and even that is being done more often by scooters nowadays. Walking is dead and you couldn't care less.

Now repeat that same reasoning with literally every other school subject...