If stocks aren't risky then why don't you leverage up your portfolio by a factor of 300% or 400%?
Because while stocks aren't necessarily risky, they are volatile.
Why should volatility matter if you don't consider it a risk? Or are you saying that volatility
is a risk?
If you are convinced that the market is going to return a certain rate over a period of time and you are 100% certain that you will be remain fully invested, it would make complete sense to borrow money at anything below that rate and then just tune out and forget about everything else and collect your excess return at the end, wouldn't it?
Volatility, and especially downside volatility is portfolio risk. There are lots of risk metrics that have been devised down the year that do a very good job of quantifying portfolio risk.. Sharpe ratio, sortino ratio, calmer ratio, gain to pain ratio, Value at risk.... There is a whole industry devoted to measuring portfolio risk.
To claim that as an asset class equities carry no risk is naive and, frankly, uninformed.
And that is just portfolio risk I am talking about. What would the community's reaction be, I wonder, it tomorrow's headline was "Vanguard group goes bust?" Not likely, granted, but counterparty risk is never absolutely zero.