These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Nausea Fuel: The sludge in the bay, which was mostly real.
Nightmare Fuel: For the first time since the first Godzilla, human death is shown graphically. Especially unsettling is that in one scene, a baby is shown drowning in Hedorah's sludge.
Signature Scene: Anyone who knows anything about this movie knows about Godzilla's flight sequence.
Some Anvils Need to Be Dropped: In Japan, in the 1970s, pollution levels were far worse than in the USA, due to rapid post-war industrialization, with no governmental checks. Despite its silliness, this movie was as relevant to the fears of 1970s Japan as the original was to the atomic fears of 1950s Japan.