Makes sense. I wasn't suggesting that one should do a shallow clone though. If your company repo is 100 GB, it seems sensible to keep it cached locally on each machine once (100 GB isn't large for current NVMe disks), and `git fetch` the updates the normal way. Then checkouts don't fetch anything large.
It sounds like it would be simple, but there are a lot of logistical issues with making git happy with this in practice. Repacking things for repo maintenance, for example, but there are many other problems.