Update: I came around more often than I originally anticipated.
I try my best to improve articles and add sources where need be. It's not easy (the fact that most of them are in Japanese and Google Translate doesn't do that great of a job makes it a lot harder), but it's definitely worth it.
I've been formally editing wikis since around 2015, even though I've been reading them since 2011.
I've also been assessing several WikiProject Trains in Japan articles recently, albeit too optimistically. Many of them, in my opinion, were either rated inaccurately (Tokyo Metro 13000 series comes to mind; it's definitely one of the better Tokyo Metro train articles out there) or have not been assessed in a very long time and now poorly reflect the article's current state.