Good story, but a misleading headline. Note the headline is perfectly correct, researchers did, in fact, find a way to steal encrypted data. . . for certain, particularly structured implementations, without remote access to the machine immediately after its been powered down with the keys in DRAM.
standard memory chips actually retain their data for seconds or even minutes after power is cut off
Okay, so they have to perform their new technique right after the password enters memory. That is less practical than other methods, for instance recording the sound of someone typing and then decyphering the password based upon keys' sound signatures.
Everybody panic, I guess?