It's easy to pick stocks in a bull market

Then why aren't the other 85% not as nearly as good? They are in the same bull market. You're mixing relative and absolute performance.

She puts the money where her mouth is and outperforms the average professional by a considerable margin. Gotta respect that.

No, I don't respect that, for the same reason that I don't respect astrologists or fortune tellers.

Nobody cares about the source as long as there is consistent profitability.Ego is the enemy most of the time, especially when you are more concerned about being right than about making money.

I don't believe in stock pickers, that's all.

Economists don't pick stocks.

Is there a law that forbids them to?

An economist placing bets on the market puts money where their mouth is, so should just write whatever they think is true.

No, nothing forbids them from picking stocks. The skills related to picking stocks are completely unrelated to the economics profession.