The roots of deep learning are from around the same era, if not a bit earlier - it's just that we didn't have the computing power to do much with it so DL kind of languished until ~15 years ago with the advent of capable GPUs. Is ART important? Can it do what DL does now? Hard to say. A lot of money and effort has been poured into DL to get it this far. If ART had gotten the attention/investment instead would it be where DL is now?