It is true that many Japanese people do not expect people from other countries to know each and every one of their customs, but I do believe that following the minimum requirement would make things a lot easier. I guess the easiest thing is to not draw too much attention to yourself, and follow the signs. With that, most should be just fine!

But the way that you've presented these facts can seem a little standoffish to some, as everyone here is learning at their own paces and some do not even have the opportunity to visit Japan.

Sorry but you come of as kind of a know-it-all/showoff.

Even more so since young japanese people don't really care about these "rules".

Especially the bowl thing, seen many adult japanese who also don't lift the bowl. (Even though they normally though).

Also, as a gaijin you can get away with following none of these rules as the japanese people in general don't expect us gaijins to know about them. So please get off your high horse lol

Don't you think this kind of thing would be better coming from an actual native of Japan? It would be kind of strange if a young person from another culture wrote a similar piece about American traditions. Additionally, the way you chose to present the information was fairly aggressive.

And there is no "have to" about the second point. Some people bring their dishes all the to their mouth, yes; in fact, my host father ate like that. However, it's more of an exception. It's far more common to hold the bowl in a fairly relaxed grip about halfway between yourself and the table. This is is my host mother, sisters, and I all ate. 

I have no comment on the first and the second issue.

For the tierd I wold say, please do wear seat in even in the backseat in Japan.

Because Japanese Road Traffic Law says that a car-driver cannot take any passengers without seatbelt. In violation, the driver may be charged a penalty point to his/her licence in the worst case. So a taxi-driver will request you to use the belt, and you'll insist not, he/she will ask you to find another one. It's a possible case.

Even though you won't care about your life, please refrain from troubling your driver.

Yes todd but this is a little obvious that you would be quiet on a train anywhere, plus shoes inside is commonly none even if you are not learning Japanology you would know this from many Japanese youtubers, and anime.