Yes, it looks like Japanese government just reminded about the position they always had that southern Kurils were occupied by Russia illegally. But the timing of the reminder is interesting.
It seemed slightly delusional (but mostly harmless) to me at the time, but now - who knows?
I don't think even the Japanese government wants them back at this point, Hokkaido (the nearest big island) is already rapidly depopulating and having to administer a bunch of semi-frozen islands with random Russian pensioners and no resources aside from fish would be a logistical nightmare and permanent drain on the treasury.