Earlier quoted context omitted.
When I visited Japan I was astounded by the high price for animation. I naively expected that buying from the source would be cheaper but... think 5000~7000 JPY for one DVD disc of a seven disc series. For DVD at least, Japan is region 2 (same as EU). I don't know about Blu-ray.
Japan is the same DVD region as the EU, but you can’t play EU DVDs because Japan players are NTSC instead of PAL in the EU. Which is probably what the GP was referring to?
I think decoding NTSC is a subset of what's required to decode PAL, if I remember my electronics classes well enough.
Or, searching around, it might be because region 2 DVD players had to support PAL, NTSC, 50Hz and 60Hz. Region 1 is only 60Hz NTSC.