Sharing one's own work here is a great idea for getting scripts/plugins out to the people who need them. It's a way to build exposure and help the 3d community.
Sharing a link to a script you have found useful to your workflow is also a great way to help the community.
Sharing the file of a script you didn't write will only cause problems. Scripts may get updated, and the official current version is unlikely to be updated here. There are also legal issues involved. So if you find something great and want to share it with everyone, do everyone a favor: share the link, not the file.