A lot of them are not common sense at all. Even the 'serious' ones require cultural knowledge to understand. Only a subset of the rest would be un-ideal across cultures, which is what I would use to measure 'common sense'.
It's like how in some asian cultures it's rude to bring the bowl closer to you by lifting it off the table, and in others it's the opposite. And of course there's some just-so story for why, that seems to make sense if you don't know about the opposing just-so story.
Things like that aren't what I'd call common sense.
A quick Google search will turn up hundreds of results corroborating this.
2. The two listed as "serious" are related to Japanese funerary rites, and so are clearly culturally specific.
3. Several of the things listed are perfectly acceptable in other chopstick-using cultures. Many are also perfectly acceptable to do with a fork and/or knife in cultures that use forks and knives. I think I would go so far as to say that there is not a single thing on there for which it would be widely considered rude to do in all cultures.
There are people in Japan who are rude or who do not have as good manners or etiquette when they are eating alone!
If everyone followed all manners all the times they wouldn't really be encoded woould they?
I suspect it mostly affects left handed people.