There's a growing subset of blocks that we may contemplate creating that are either more niche or—for various reasons—not necessarily an immediate fit for the bundled library in core. [Some examples.] This would include blocks that have enough appeal, demand, and where offering an endorsed implementation can significantly help both creators and viewers given best practices can be ascertained.

I propose we look at a mechanism where such blocks can be designed, developed, published, and maintained by core contributors in this repository (benefits from collocation and testing infrastructure) but for them to be published as standalone blocks in the directory instead of bundled in the default library. These blocks would show up as authored by [WordPress.org]. It'd allow themes and patterns in the directory to leverage them with certainty.