"It's been a long summer, but now winter is coming", akin to every time the markets have gone up, hit their peak and then declined (all with different time frames). Similarly, interest rate will be going up broadly across the developed countries and long bonds funds will suffer losses, so time to look at the short end of the fixed interest market - secured debt will be better than holding corporate bonds (given they rank higher on the capital return structure).
I have been researching and changing my recommended portfolios for clients in the lead up to the market movements - mine was the first one I changed. The most difficult time will be in the first year of the downside for retirees, when returns (whether capital and/or income) may not match their minimum withdrawal rates, so a decline in capital is likely. But their downside will most likely be lesser than the markets (depending on their asset allocation). May be closer to 1994 than 1987, or 2000, or 2007.