While I understand the science behind the release of the wastewater; I also really do understand why people are so willing to ban this.
It doesn’t matter if it is safe to eat or not. People have a right to not partake in fish from the Fukushima area. Nobody should have the right to conceal origin information about food items in general, particularly not when food may contain things that are potentially impactful to a person’s health.
40 μSv might be a “Safe” exposure over time; but that doesn’t mean it’s completely without health impacts. People are within their rights to avoid that extra dose if they feel the risk is unnecessary; no matter how small that risk may be.