This, is 100% FALSE. Activity and chance are, well, parallels. "Better chance to profit"? If activity(as in price movement) means chance then the trading is flawed. if there is no activity, the trade is wrong. If there is activity and generates loss, the trade (assuming entered for profit) is wrong. Activity is not chance. Such trading is flawed. Again, chart reading ability and execution mechanics are unrelated to volatility. Volatility does not change the "how" a trader or computer analyzes nor does it change execution mechanics. However, it may change "why" or "when" a trigger is generated.
Your buy and hold case in point is textbook for why long(er) term market participants shy away from volatility.