Yes, the article seems to be not detailed enough. They show the pictures, and it is evident what the pressure release valve is, but I agree that by this logic any container or any steel water bottle is dangerous. Maybe there is some other additional feature that makes it particularly dangerous compared to other models (like, the new seal keeps higher pressure, or the lid needs fewer rotations to disengage, etc.) that is not explained here and makes all the difference. Older models didn't even have a pressure relief valve, did they?

> is there some expectation that it should have pressure release?

Scroll down in that article to the section with photographs of "recalled" and "not recalled" lids side by side.

The whole point of Thermos is to keep things warm for a long time. That means pressure. It's a basic safety feature.

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