Libraries have licensing requirements that your company needs to comply with. Being able to download and use them without any oversight is an recipe for violating them.
it's absurd to me that you'd need to put every library through compliance even if it has very straight forward OSS licenses.
There was specific software everyone could install with a service request, non-standard software could also be requested, temporary rights to usual stuff could be requested as could permanent access to those rights.
It was just annoying for me, but I could see it being a significant impediment for some people in some situations.