Yeah, compared with the maintenance effort of running around to 100 different repos, keeping everything in sync and the deps all updated, I'd always take the pain of 50GB checkouts.
It looks like these days a combination of git-scalar, git-lfs, and bazel will work for a small 50GB monorepo like that. The largest cost would be porting over the existing build system to bazel and then integrating it with CI. Once that is done, though, the monorepo will just scale, and all the constant ongoing cost of multirepo sync will be gone.
