Rice patriotism in Japan is just result of politically motivated and generally unpopular gen-tan policy spectacularly backfiring. The price is not artificially inflated, at least not by JA, it's just result of forcing rice to be uneconomical in the market where people just buys rice no matter what. As supply is decreased artificially and price increases in response, unit price rose and so did quality. As result of quality increased artificially although indirectly, imports unaffected by local market further lost competitiveness.

I bet Japan's going to be internally forced to expand rice exports, not imports. Farmers must pay bills or else they go away, and people aren't going to eat imports. So farmers has to stay by either completely subsidized a la defense production, or by scaling out at paces permanently exceeding inflation. Maybe both. Extra production has to go somewhere but population is on decline, so it has to go somewhere beyond the seas.

Unless iPhone moment happens and the country's hit by vastly superior rice, which iOS was - iPhone had worse hardware with worse integration than any of local phones back then, but UI/UX was literally 5-10 years ahead of everything else, and it completely replaced the entire Japanese phone market helped by blatantly illegal marketing tactics. That's not happening so far with rice.