Stop losses do reduce losses but in some scenarios where a signal has been given(with a limit order, take profit zones and stop losses zones) and the price does not reach the take profit zone then drops to the stop loss zone, the profit that could have been raked in is now turned into a loss. All due to not knowing a at least basic knowledge about the market. Mind you, I was talking about people who barely has knowledge about the market and relies alone on signals. This includes most basic indicators let alone trading plans nor portfolio plans.
People who barely know how to read signals should not be using any stop loss or any other method and should stay away as further as possible for the time being. Market is already losing blood and it is basically just a situation where even veterans are leaving and not trading like crazy right now, and that means that if we could stay away from it as long as possible until it gets better than it is better.
If we learn about signals and be great at finding where to buy, then even the signal could come to be a wrong one, because market could move hectically without caring about the indicators. So, it is best to stay away for the time being.