A thought occurred to me with the increased rise of English releases and the boom of collectors. We’ve already started seeing people priced out of their initial goals and some people are turning to Japanese product to have their goals met.
With this being the case and the number of cases where this occurs slowly rising, I wouldn’t doubt it if we saw a boom within the next few years on Japanese cards just because of people turning their attention towards it.
I imagine it’ll work out a lot like this: Grading services and selling via graded is established as norm > English prices rise for raw and graded cards > Attention turns to Japanese cards > Japanese prices rises for another 5~10+ years > Fallout of collectors as older sets become too much for many except for the few who can afford it > Focus on Modern and modern only with reserves for a few “holy grails” sprinkled in the mix.
Granted I imagine the entire time span realistically for all of this will be in the next 10~20 years, but I wouldn’t be surprised if we see it sooner since we’re entering that 3rd phase already.