Trademark law isn't about what "everyone already knows". It's about whether a given mark meets the criteria for legal protection in a give context. So if say an foss ML project described what they do as "open AI" the company known as OpenAI would have a right to defend the mark. This is saying they could not.

> So if say an foss ML project described what they do as "open AI" the company known as OpenAI would have a right to defend the mark. This is saying they could not.

Well if that's all that's at stake here, it seems very reasonable.