Monorepos have a U-shaped utility function – great for small and large projects, difficult for mid-sized ones. But there aren't many good monorepo frameworks out in the world. Lerna is deprecated, and even new upstarts like Turborepo are getting absorbed (i.e., acquired) into other companies (Vercel). Likewise, centralized version control tools like Perforce and large-scale build tooling (buck, bazel, pants) have struggled with adoption.

As someone who continues to manage projects in a monorepo format, I often ask: why isn't better tooling available? Some hypotheses.