Not quite. I’d seen information about fermentation-related carcinogens, but like the article says, I haven’t come across anything suggesting this is problematic unless you eat a lot of this stuff every day (like the people in China who were a part of the study mentioned in the article).

I linked to an article pointing to heavily salted, preserved foods being correlated with stomach cancer in a response to another comment. Though salted fermented foods fall into this category, so would things like jerky or salted olives for example. It isn’t clear to me what should be avoided necessarily, though it seems like decreasing sodium intake is a net positive regardless.

In any case, I think eating these foods is likely okay or even healthful so long as it doesn’t make up a large part of your diet.