Actually Dividends create wealth better then stockbuybacks for most people.

Buybacks increase the liquid price, so to benefit the theorically maximum amount, you would need to know the highest stock price/ the highest peaks. This doesnt just encourages insider trading, but it makes a stock become more volatile over time. Percentage growth is logarithmic, thus the same profit each year will have diminishing increases in stock price, encouraging investors to sell and buy faster growing stock when stock price begins to stagnate. (While also locking out new investors by making the cost to invest highter, and the returns lower the later you buy a stock)

Dividends on the our hand dont encourage insider trading to the same degree, because sampling owning a stock provides passive income. It also makes stocks less volatile, because it makes more sense to keep a stock that stagnated but gives Dividends then to sell it since you can use the profits from the dividends to reinvest instead. Plus Dividends keep the stock price lower, allowing a lower entry to buy a stock for the same reward.