I've not really read all the posts here so forgive me if I'm wide of the mark.
I've had a few thoughts ref how cultures are different and if it would be possible to change certain attitudes and behaviours to the environment and litter etc.
As an example I believe the Japanese don't employ Caretakers in the primary and secondary schools - instead the children are expected each day to maintain the cleanliness and upkeep of their school environment as they have from day one a vested personal interest in its state of upkeep.
I believe this upkeep mentality then extends into their mature adult life and as such littering in society isn't an issue.
There are LOTS of difference between our cultures and theirs would seem to be far more the collective rather than the western way where individual believes they are sacrosanct. But I do wonder how much positivity and maybe how quickly that ethos could be ingrained in the next generation if it was allowed to be implemented if needed.
But something like the concept of the environmental DAVOS driven 'Great Reset' maybe pushed upon people sooner rather than later.
I don't think you can pick that specific cultural characteristic out of Japanese society on its own TBH. Japan has the lowest (I think) intentional homicide rates in the world and one of the lowest crime rates. I believe there is a far wider level of respect for others across the board in Japan - how we get that into society I have no idea. Of course, there may be negative aspects about Japanese society that we are not aware of that affect the level of respect - there is always Yin and Yang