On one hand (heh) there's apparently evidence to suggest that handwriting activates parts of the brain which aren't typically activated by just typing something out. I can see how that would be the case and why it could sometimes be useful.
On the other, the idea of carrying a little notebook around to jot things down when I have a phone in my pocket, or using a fountain pen for longform text (trust me it would actually help you avoid hand cramps, aside from being less wasteful) all comes across as... intentionally inefficient? I struggle to see intentional inefficiency as anything but pretension. Like it's all just fetishizing living a more analogue life.
It actually makes the techbro in me think there's something to companies like Supernote and Boox and ReMarkable making e-ink tables that exist mainly so that what you do choose to write by hand can be digitized, stored and made searchable.
I suppose that's actually exactly why people tend to journal in physical notebooks? Because what you put down in there will just disappear unless you crack open that notebook again.
...Meanwhile I'm pretty sure a lot of people feel that writing things by hand gets their creative juices flowing. That's sort of interesting to me, because personally, by the time I'm finished writing a single sentence whatever I was thinking about is halfway gone. If I don't get it down real quick my thoughts will drift to something else entirely, so when I had to handwrite essays in primary school I'd get completely stuck in a way I never do just typing things.
TL;DR someone who's bad at empathy talks about handwriting as if everyone else experiences the world exactly the same way, please knock him off of his stupid pedestal
I like to do both. There are times where I need to type everything, because my typing speed can keep up with my thoughts. I can get all of the thoughts out of my head quickly, and clear my head so I can focus. It's also easier to do in some places, like when I'm at work - typing myself a quick note and then emailing it to my home email (or saving it in drive), is much faster and more likely to make it where I need it to go. I tend to forget physical items at work.
Writing by hand I use for journaling. For slowing down and taking time to do something. For magic - where I want to put intention and energy into the words and sometimes burn the paper after. For when my eyes are so sick of screens that I just need a break, but still need to get those thoughts out. I'd also rather handwrite something then type it on my phone - Eventually I need to get one with a stylus so I can just write on the screen.
It's the same reason I usually draw things by hand, then scan them to digitize. I have a tablet. I use it for digitization. But my art is generally better by hand.