Which is fine with for example OpenBSD, they write “ISC or Berkeley style licences are preferred, the GPL is not acceptable when adding new code, NDAs are never acceptable. We want to make available source code that anyone can use for ANY PURPOSE, with no restrictions. We strive to make our software robust and secure, and encourage companies to use whichever pieces they want to.”
Which is fine with for example OpenBSD, they write “ISC or Berkeley style licences are preferred, the GPL is not acceptable when adding new code, NDAs are never acceptable. We want to make available source code that anyone can use for ANY PURPOSE, with no restrictions. We strive to make our software robust and secure, and encourage companies to use whichever pieces they want to.”