As a matter of fact, I am (in the computer security vertical) - look for an announcement on Hacker News at the beginning of the year. I suspect that others are too, but there's always a discoverability problem for niche tools in verticals that one doesn't participate in, e.g. I know nothing about software for dentists but I know that at least one exists, and that there are probably a lot of dentists who use it but resent the fees, features or support, and there are probably some dentists who could manage an agentic coding project.
There have ALWAYS been niche OSS projects, and agentic coding will make them better and more prolific.
There are people like me who are passionate about a space and have the skills to manage an agentic coding project and the domain knowledge to design the software that they want, but not the skills and time necessary to have built the software in the absence of agentic AI. Last year I would never have started my 100k+ LoC project. This year I am proposing colleagues at two Fortune 50 companies to adopt it (at zero financial benefit to me). I am doing this from love of the problem space and desire to improve software security across the industry.
The vertical I'm in has zero overlap with the developer population. The end users aren't technical, don't participate on HN, and aren't going to "manage an agentic coding project." There's no equivalent of a developer who moonlights on OSS tooling because they're passionate about the problem space, because the problem space requires domain expertise that developers have no reason to acquire.