i think most people portfolio will be red unless the portfolio is heavy on Energy sectors, but i dont think anybody will do that, energy sucks long term.
if the investors pick stock simply by listen to youtubers and do not know how to valuate the buisness. Then 3 fund will be a better choice.
Also many new investors overestimate their ability to handle the market volatility when market crash 20-30%, they panic & start to buy and sell things.
The best thing to do when market down is actually buy more, the second best thing is simply do nothing. The best trading days normally come right after the worst (If you had read about the research of missing x best days = missing ton of returns)
Although i pick stocks, but i cant deny the facts the benefits of 3 fund, it help dampen the drawdown.
Personally, i dont really care about market volatility, but i do care about growth, cashflow every month & i dont like to actively manage my portfolio. Thus i got US & sg dividend stocks, option trading not my style.