Carolling largely follows a bimodal distribution based on social class. It's still reasonably common among lower-working-class kids looking for a bit of extra pocket money before Christmas; for similar reasons, they're the last stalwarts of the penny-for-the-guy tradition. It's very common for those at the upper reaches of the middle class, who have a real penchant for old-fashioned community activities like choirs, fetes and street parties. It's all but dead for the majority in the middle.

Speaking more broadly, there has been an effort in many rural areas to maintain and revive particular local cultural traditions. Perhaps the most spectacular such tradition is the tar barrels in Ottery St Mary[1], but I'm also rather fond of the Royal Ashborne Shrovetide Football game[2] and the multitude of mumming and wassailing traditions[3].

[1] https://www.youtube.com/watch?v=N8-0wQmPeMg

[2] https://www.youtube.com/watch?v=5uV1zrZFzZo

[3] https://www.youtube.com/watch?v=PEDaRQO5Utk

How on earth did the Tar Barrels become a tradition?! :o

and the Shrovetide Football with only 1 rule?! :'D That's insane!

Only in England! I miss you guys :D

Well, obviously I've been gone for 20 years, so I can't speak to whether they still happen but growing up in the village I did, they happened every year without fail. Some years we'd go with them, other years we'd stay home and have hot mulled wine to offer them when they came around.

Another thing I struggled to find this year in my local area was midnight mass. This just doesn't seem to be a big thing here either. The best I could find was a 10pm mass, which just doesn't seem to cut the mustard... plus what's with the singing carols to the wrong tunes?

U.S here. I know carolers who get together and go through hospitals and retirement communities. Definitely a nice way for children and teenagers (who come with) to learn about giving back to a community.

Canadian here and these happen in my neighborhood. YMMY elsewhere, as OP has mentioned.

Canada is a big place, which city are you in?

One of my family members would go with a group caroling in Winnipeg.

I can't say they're common, but they definitely happen. We usually get 1 or 2 small groups each year.

Lived in the UK for a few decades. Have never seen a carolers. Thought they were a weird USA thing.

Not only in the UK. Carolers are a thing in other places of Europe, for instance Greece.

In Portugal we have "singing the kings" in the first days of January, and traditionally people shared the Christmas food and drinks with them.

https://youtu.be/JlBnLlKPPGA?t=11