"Do not resell or redistribute the icons, even for free." But they gave them the MIT License, which explicitly allows those things...
I cannot understand how the authors think this is valid.
I imagine the author is trying to do open source well by using a license but doesn't fully understand the impact it has on the project. That's fair enough, and very common when people are new to open source.
[1] https://github.com/mikolajdobrucki/ikonate/commit/5993f43ce6...