It's interesting that you would name Cisco. They hired Kent Dybvig and acquired Cadence Research Center in 2011 for Chez Scheme[0] — possibly for use in processing IOS configs, testing, and network management. It seems like Chez was the most performant scheme in the day[1] and was proprietary, expensive, and possibly not available to individuals.[2]
There were a number of good free schemes[3], and Chez was open-sourced in 2016, but I wonder how much of Perl, Ruby, and Python's popularity derived from their open licenses.
https://web.archive.org/web/20061205234158/https://www.cs.in...
The Scheme Programming Language 4e
https://www.scheme.com/tspl4/