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
> All the packages I've listed do not have any free-quota restrictions so they don't require a paid Developers license to enable unrestricted usage, since they already don't have any restrictions.
How does that line up with your license that states "small projects and evaluation" only?
I'm not doubting that your intentions are for the licensing to be as you state, but that's not what your license says :)