They often repackage a shit ton of open source software developed by volunteers, all of which is running on Internet standards originally developed by the Department of Defense for military use. Most of the tech in the servers was developed by various DARPA initiatives surrounding transistors and solid-state memory.

Mind you these things were invented at companies, yes, but almost every time if you dig deep enough you'll start finding the lists of the various grants given to said companies to fund this research, because otherwise they just tend to not do that. This is not controversial stuff, it's very normal.