That's my point -- there's no clearly good place to put money right now -- no place where you can have near certainty of getting back significantly more money, in real terms, than you put in. At best, for low risk you wind up betting on a fraction of a percentage point of real gain. That wasn't always the case. There were points at which CDs, treasuries, etc., paid multiple percentage points above expected inflation.
I've got my cash sitting in a Fidelity Money Market, which is only getting 2.09%, which is effectively a money-loser after expected inflation. But, I've still decided that's better than putting it in a six-month CD, at least unless I can get over 3%. With rates more likely to rise than fall in the next six months, I think I'm likely to get a bit better than 2.1% in that period, and in the meantime I have quick access if an emergency were to hit. A fraction of a percentage point for half a year, for the amounts I'm putting away, just doesn't add up to much.
I would say "it's probably not negative income." In theory, it could be negative income, in real terms, if inflation comes in just a little higher than expected over the next six months.
Inflation needs to be accounted for if you want to know what the real return is. Just take it to the extreme to show the point. Picture, say, 1000% inflation. Well then, I'd definitely be better not to lock up my money at a low rate for 6 months, since I'd lose nearly all that value, in real terms. I'd do better, then, to buy some tangible object that holds its value in real terms, or just to put it in an account with a floating interest rate, which is likely to rise in response to inflation (or, say, a TIPS investment). Granted, we're not going to see 1000% inflation, but the concept is still there, just more subtly.