> It says all products are restricted as stated there.

It does not say this, it says:

> Licensee is granted a right to use the Software for small projects and evaluation purposes without charge provided that use of the Software is within the "Free Usage Quota"

The free usage quotas only exist on the commercial products which I've already linked to https://servicestack.net/download#free-quotas

On the free products pages, like ServiceStack.Text product page [1] and GitHub project page [2] and #Script home page [3] all specifically mention they're free to use. Whilst all of ServiceStack's non .NET libraries like the JS/Typescript clients [5], Swift [6], Java/Kotlin [7], Dart/Flutter [8], CefGlue Support, etc are all published with liberal BSD/MIT OSS licenses.

[1] https://servicestack.net/text

[2] https://github.com/ServiceStack/ServiceStack.Text

[3] https://sharpscript.net/#free

[5] https://github.com/ServiceStack/servicestack-client

[6] https://github.com/ServiceStack/ServiceStack.Swift

[7] https://github.com/ServiceStack/ServiceStack.Java

[8] https://github.com/ServiceStack/servicestack-dart

[9] https://github.com/ServiceStack/ServiceStack.CefGlue