Based on the article, the device will host actual kidney cells - I’m sure it won’t be as effective as having your own original kidney, especially in it’s early prototypes, but hopefully it’ll be better than mere dialysis.
Even if the device was just a glorified portable dialysis machine though, that would still be a significant quality of life improvement for those on dialysis. With dialysis you’re locally tethered to the dialysis clinic because you need weekly treatments, until you eventually die or win the kidney lottery. With a portable machine you could hopefully travel, see the world and visit family more.
Be kind to your kidneys everyone, drink enough water! You don’t want a life without efficient kidneys.