A company where six people post in the founder's voice is a company where five of those posts are obviously ghostwritten, and the audience notices before you do.
The value of a team posting is that several credible people are visible, each with their own angle. If they all sound identical, the audience correctly concludes that one person or one tool is writing all of it, and the credibility of every account drops rather than just the ghostwritten ones.
Distinct voices are also easier to write. A profile that says this person is architecture-first and opinionated gives a writer something to aim at; a profile that says professional and insightful gives them nothing.
Individual voice governs register, structure and opinion. It does not govern accuracy, claims, or whether a client can be named. Those sit in a shared floor that every post meets whoever wrote it, so voice variety never becomes a route around the standards.
When a team member's post is a version of something the founder published, the original is retrieved first and the rewrite works from it. Writing from memory produces a post that is about the same topic and has quietly lost the argument.
Skills compound. These are the ones we usually install alongside it.