So, Finland is phasing out handwriting classes in favour of computer typing ones. Is this a good idea?

I don't think you can say no or yes, straight up, but if my guts were to choose, I'd say the keyboard can eat a dick; from this article:

Handwriting is better because it slows the learner down.

By slowing down the process of taking notes, you accelerate learning.

So guess what, you learn better as you write, because you most likely won't write down everything, but instead, you take in what's quality for you and you note that. Wee! Also, you gather your thoughts in more ways than one as you're handwriting something. When you're typing text, you just see this standard font, which is kinda prefunctory. You use your handwriting, you will no doubt sketch and pluck away more than you would by using a computer. And don't get me started on how great writing by hand is where creative writing comes to mind.