Arden Arcade is just one of many, many urbanized unincorporated areas in California. Our community is part of California (un)Incorporated, a coalition of communities across the state that don't have a Mayor and City Council to focus on local priorities, whose municipal affairs are managed by a county Board of Supervisors overwhelmingly composed of people neither connected with nor elected by local people, and where there is no local control over taxes paid for municipal services.
One of the challenges in advocating for an unincorporated community is that many people do not know what an unincorporated community is. Several communities in the bayside core of Alameda County - Ashland, Cherryland, Castro Valley, Fairview, Hayward Acres and San Lorenzo - are heavily urbanized unincorporated communities like Arden Arcade. Some of the Castro Valley people have produced a video (first in a series) that tries to explain things. You can see it at: https://vimeo.com/536543942. It's worth a look!