Seems like the Japan stations don't use LoTW. I have a bunch of contacts with and not 1 confirmed by a Japan station.
For the most part I like LoTW and use it exclusively now.
I checked and my LoTW has 998 confirmed Japan contacts from 1992 thru this year, out of 3500 or so in my log. So some of them do use it :-)
Whatever dude...no need to be snarky. Just sharing my experience.
I have 10,000-12,000 mile SSB contacts confirmed using a BTV with an AL-80 amplifier.
I am proud of my confirmed contacts from my modest station because I earned them.