It's shown in 180 countries worldwide and very popular internationally (Including Russia):
https://bigbangtheory.fandom.com/wiki/International_broadcas...
While I don't necessarily love the show, I've known many PHD students from China, Taiwan, and Korea that absolutely love the show. Hardly from countries that "don't value intellect".
"This permeates western culture across the board,"
I can't speak for Australia, but I went to high school in the US during the 90s. The 'cool' kids weren't necessarily anti-intellectual, they were just more social and were well versed in the ability to make friends. Most were in the top 10 in terms of grades at our school and I didn't go to a specialized or private school.
The 'nerds' and unpopular kids weren't necessarily smart either. Many had Aspergers or were on the autism spectrum, which means they most likely won't do well in social situations and most likely won't ever be popular.
Others were just anti-social or were just never taught how to make friends or be a friend.
Sheldon from the Big Bang Theory is supposed to depict someone like this.
It's easy to say we aren't popular because we are smarter than everyone else, but the actual reasons are much more nuanced.
"The other factor is that westerners really love to coddle and infantalise their children. A 12 year old in Russia is basically treated as a small adult with the associated respect and responsibilities. A 12 year old here is treated (and behaves) like a large baby."
I suppose this is just the result of living in a stable and safe country. 12 year olds aren't adults and shouldn't take on adult responsibilities. It's sad to me that there are children out there that can't actually be kids for awhile, which is something you can never get back as an adult.