Self ping for later. Good comments.
The peak or “inflection point” is actually less about fact and more about perception. Meaning, when citizens perceive their tax money is spent wisely, and the need is real, then they will tolerate a higher peak. When citizens perceive waste, the peak is lower. Hence, in WWII citizens not only tolerated high tax rates but they bought war bonds (e.g., more financing of government) and worked harder in spite of the higher government collections. But when citizens perceive waste they will do anything to avoid taxes including investing in non-productive investments, just for the satisfaction of thwarting the government. Others will go so far as to hide income and risk tax fraud.
So the peak is not a fixed number but will vary depending on the party in power, the cultural and economic conditions, and citizens’ general perception of fairness.
Politicians are the worst in this regard. I like the story from Massachusetts, where liberal members voted in a higher tax on alchohol so as to fund their pet projects, and ignored pleas that it would hurt business and not raise revenue. A few months later, one of the key Dem legislators was caught avoiding state taxes bringing a trunkful of booze across the state line from New Hampshire. Touche.
Readers Digest did a survey years ago as to what a “fair” tax rate might be. The answer, from all income brackets, was about 20%. I think that the starting point for Laffer curve inflection point discussions should be there.
If it is obvious to you, you should publish your findings in a peer-review journal.
First, at least at the federal level, we have to dump the concept that taxation is about revenue. It isn’t. The federal government could just print more money - creating an implicit tax on everyone through inflation and get by perfectly well. Taxation is about control. For every dollar the government takes from you, it takes away the freedom to spend that dollar as you wish. You lose a little bit of liberty with each tax dollar taken.