The 70's were up and down, but from Jan 1 1970 to Jan 1 1980, the net increase in the stock market was a 22.7% gain over the 10 year period (as measured by the S&P 500). That works out to around 2.1% annualized gain, which isn't very good, but that's taking the "bad" that allows you the opportunity to get the "good",
Jan 1, 1980 110.90
Jan 1, 1979 99.71
Jan 1, 1978 90.25
Jan 1, 1977 103.80
Jan 1, 1976 96.86
Jan 1, 1975 72.56
Jan 1, 1974 96.11
Jan 1, 1973 118.40
Jan 1, 1972 103.30
Jan 1, 1971 93.3
Jan 1, 1970 90.31
The next 10 year period, the 80's, featured the S&P starting on Jan 1, 1980 at 110.90 and ending on Jan 1 1990 at 339.97, a 206% net gain, or 11.9% annualized. Better than sitting on the sidelines worrying about volatility.
Jan 1, 1990 339.97
Jan 1, 1989 285.40
Jan 1, 1988 250.50
Jan 1, 1987 264.50
Jan 1, 1986 208.20
Jan 1, 1985 171.60
Jan 1, 1984 166.40
Jan 1, 1983 144.30
Jan 1, 1982 117.30
Jan 1, 1981 133.00
Jan 1, 1980 110.90
I'm not saying anyone should go "all in" on equities, but there is no question that over time, being overly conservative will cost your portfolio greatly.
Then again, I embrace volatility, as I trade options for income as a profitable hobby. My risk tolerance is probably greater than that of most people, and probably a little more than it should be.