The Japanese are very traditional and their traditions are rooted in religion.
Finland... something like 65% of the population is Lutheran, and that number was 90% in the 1980s. So it seems like the bulk of the current happy adults were raised in a religious environment even if they are now losing it a bit. Interesting to see how well they will persist in the future.
> something like 65% of the population is Lutheran
Most of those entered a church a handful times in their life, they aren't practicing Christians they don't believe in any god and don't care about it in their lives. Churches remains empty most of the time in Scandinavia, they are everywhere and welcome people but nobody goes there since they don't care.
The reason people registers with the church is that it gives them an place to marry in and it pays for their burial. It is a transaction and not a religion nowadays, the church owns all these huge buildings that exists everywhere, often the largest gathering place in town.
We even have practicing priests here who doesn't believe in God, for example 25% of priests doesn't believe that Jesus resurrected. Their job is to take care of the church and preach to the choir, not to believe in anything. There aren't enough believers to fill all the priest positions, that is how low our belief is.
Same in the UK, Church attendance has gotten a bit of a boost due to immigration but they are generally on the decline, and many are converted into houses or businesses.
I do think those religions are safe refuge for "atheist" tendencies and would agree with your point.
It's funny that I attended a Christian school when I lived in Japan as a high school student, but never spoke the language well enough to have any really deep spiritual discussions, sadly.
My understanding is that the Japanese are rather keen on following (or adopting) religious rites without being believers. A modern Japanese person may have a Shinto coming-of-age ceremony, marry at Christian church, and have a Buddhist funeral. All without really being Shinto, Christian or Buddhist in any meaningful sense of the word. In fact, I would argue this superficial syncretism happens precisely because of their lack of belief in any of it.
Sure, if you look for them you will find some devout Japanese, but they are very much in the minority. In every practical sense, the Japanese are exceptionally secular compared to e.g. the US.
They're a mostly atheist population.
See also Estonia, Japan.