Technical indicators are filters. It is hard to say the filters are good or bad. It depends on how people use them. As for predictions, all predictions are based on historical data analysis and back testing. Predictions could be mathematically meaningful. But prediction and real trading are not the same. I can write a book to answer your questions.
Program Trading is based on historical data analysis or so called Technical analysis.
Have you heard Goldman Sachs, the largest program trading firm in this world?
Check how much money they made in 2009 by Program Trading.