(https://en.wikipedia.org/wiki/William_Jones_Cup)
Maybe yes, Japan already good with their journey after being qualified to the upcoming olympics it might be good for the team to focus with their journey and maybe they just sending players but not those from the national squad, while SGA is really doing good having that winning streaks, like what you said the chance of winning the title is possible and that's a good relief after being short from the last OQT.
Honestly, I think the current lineup is better than the players who played during the Olympic qualifier. You can see a lot of imports in the SGA team now, unlike the Olympic qualifier where we only had one, Justin Brownlee, our naturalized player. Maybe that's the reason why we are dominating the tournament and are very close to winning again after the 2019 success.