What kind of returns can you expect on your investments?

So many investment articles, personal finance textbooks, online calculators, and advisors plan for future returns to be similar to past returns. Much of the research I've been reading over the past few years suggests a very difference future with much lower returns than historical levels. Recent low levels of bond returns due to low interest rates are a factor.
"A MFS Investment Management report predicted that a hypothetical portfolio of 60% equities and 40% bonds could see a 10-year annualized return of about 3.6%, compared with 7.2% seen over the past decade." (Retirement Security Smartbrief, 1/24/20).

According to Jon Barry, senior retirement strategist at MFS:
On the equity side, “We feel good about sales growth and dividends, but we don’t feel as good about corporate margins and profits and just valuations in general,” he says. “Stocks are trading at a very high price-to earnings ratio, and we don’t see that as sustainable. With the trade wars, and as unemployment remains low and wage growth cuts into margins, companies will be restrained.”As for fixed income, Barry says, “Rates are historically low, and we don’t see anything in the near term that will make rates move higher in a meaningful way. Starting yields are a good predictor of where returns will be. Treasuries are yielding around 2%, and it’s not unreasonable to expect the same,” he says. 
https://www.plansponsor.com/consider-conservative-investments-pre-retirees-hold/

So please be realistic when projecting future investment returns as you plan for retirement and other financial goals.