The RX 470 came out less than 3 years ago. >_>
If you want a graphics card upgrade though, it depends a lot on how much you are willing to spend, and what resolution you will be gaming at.
If you want a noticeable performance improvement, you will likely be looking at something in at least the US $200+ range though. An RX 580 can be had for less than that, but is only around 25% faster. For a little over $200, you could get something like a GTX 1660 for around 50% more graphics performance than your RX 470, but if you want an AMD card in the $200+ range, I would probably wait some time and see what AMD's next generation of cards has to offer, though it's not yet clear when the more mid-range offerings in that series will be out. Probably some time within the next few months. So far, they have only launched the RX 5700 and 5700 XT in their new series, which are priced in the $350-$400 range. If you are gaming at 1440p resolution, those might be good options, but at 1080p they are probably overkill.