As I've said above, only OSS projects that create custom builds from source use the AGPL/FLOSS license, the license was added to allow OSS projects to use all of ServiceStack without needing to pay for a developers license.
All other usages of ServiceStack from its official NuGet packages are only available under its commercial license which only requires a paid developers license for its commercial products that contains free-quota usage restrictions [1]. The rest of ServiceStack, inc. all core and client libraries like ServiceStack.Text, ServiceStack.Common (containing #Script), ServiceStack.Client, etc are all unrestricted libraries that are available to use graits/for free.