UnthinkableSplitWise has an interactive webpage where you can set tax levels and see what effect they have on revenue. It is fun. I recommend that you check it out. However, it is interesting how it constrains debate. You can only change the top tax rate up to about 48%. Note that only 30 years ago, the top marginal tax rate was 70%. Now, people who create interactive tax tools think that any tax rate above 48% is unthinkable.

The sad thing is that this was probably not intentional. To the creators, a 70% marginal tax rate was literally unthinkable.