I worked in a huge big tech with infinite resources. They say monorepo using bazel and gazelle is a success there, I personally found it the worst dev experience ever... Everything was so slow, IDE doesn't work properly, there was no easy debugger, intellisence, refactoring, Code generation... Now every enterprise which calls me on LinkedIn, I ask if there is usage of monorepo, if it has, I just answer that I am not interested...