You can find these in western Canada too: https://www.elitejetsetter.com/snow-ghosts-big-white/amp/

Non-AMP link: https://www.elitejetsetter.com/snow-ghosts-big-white/

I've thought these frozen and snowed trees are common in all mountains.

Yes they are, you just need brutal enough weather with strong winds and can see this few times a year

I wonder how many things like this technically exist but which simply don't have the necessary circumstances to exist on earth near humans by complete chance.

I visit Yamagata every year. I love how in Japan each region has their own specialties, it makes it fun to travel within the country. It would be sad if the snow monsters disappear.

I usually visit in the summer. The mountains are incredibly verdant. I love riding my bike there. Just watch out for the heat at that time - bring plenty of Pocari Sweat!

These are common in northern Finland as well. The phenomenon is called "tykkylumi" in Finnish.

I sheltered at the base of these things once, we reached the summit and the wind became quite intense. It was too cold and windy to get our skins off to ski down. We couldn’t see anything either. We huddled in the hollows that formed around the downwind side around the base and got changed over and then Ski’d down. In hindsight it probably wasn’t dangerous as we were dressed for it, but it was scary, the wind was truly formidable. We lost a few items that flew away.

They are enormous in real life and it’s amazing the trunks don’t break as they sway in the wind.

Worth seeing in real life if in the area.