Could, but what for, at the cost of extra steel? They had no resources to spare for what could be in the future, they were skimping on more important things already, like their capital ships numbers and armor. They were fighting China that had no real industry, USSR that Hitler was totally sure to break in the west, and USA that was supposed to be defeated on the sea which would mean no ability to bring any tanks at all to the islands.
Also Japan did have a lot of 75mm field and infantry guns, it's just that in the jungles of SEA islands and infrastructure there, long and heavy European style anti tank guns would be a massive pain to move, everyone already had mobility problems in better terrain with those due to how hard they are to move with manpower. They should have invested in HEAT shells for what they had.