I believe people are focusing on that because that's a traditional meaning of the word — Merriam-Webster uses "concession" in 2 out of 3 definitions. I would say that an impersonal "compromise" was more of a figure of speech that evolved into another meaning of the word.

The OP here talks about a compromise between two ideas, which means that it could be a single person making trade-offs based on their conscious choices about where the (bigger) value is.

The negative connotation is also mostly personal — it's like glass half-full or half-empty question: one can say that in a compromise, two people/ideas are going away with some of their desire/value unfulfilled, or that both are going away with some of their desire/value fulfilled.