The MIT in the 70s and 80s had LANs and file servers already. The networked Lisp Machines used common repositories. There weren't passwords. Different sites shared files via tapes and via the early ARPA net. Losing this when the MIT commercialized some of the technology inspired Richard Stallman to start the free software movement.
Lisp and AI users collected and shared a lot of software. See for example this repository with software from the 80s and early 90s:
Sharing was done via FTP servers.
When Common Lisp was initially developed from 82-84, immediately open source implementations (with different licenses) were created: CMUCL, KCL, AKCL, WCL, CLISP, ... which can be traced to today's SBCL, ECL, CCL, ABCL and others.