It's only my opinion, but I'd say they may qualify as low risk (depending on the bank) in a 'normal' environment. But that's not where we are. So much more money has been printed than ever before that no-one really knows what the outcome will be. Inflation seems a reasonable expectation, in which case holding cash only makes sense in an inflation-linked interest bearing account. Even then, if the kids have flown and the mortgage is paid off your inflation rate won't bear much resemblance to the ONS figure.
Given that we're in new territory, everyone's guessing. We all want to sleep peacefully at night so it seems sensible to hedge for a while. Llike others here I'm overweight gold, silver and miners and I expect to stay that way for 6-18 months, maybe longer. Miners are the biggest segment by far because leverage appeals to me right now. But anyone can open a BullionVault account and buy metal in relatively small quantities. In a year or two we should have a better idea of what the new normal looks like.