9070 is going to be significantly faster, but I would not expect a performance jump of 70% in games, at playable resolution and settings. There might be a few outlier titles where it gets close?
If you have already tuned the 12600K, the next suggestion to address the hotbox, is use a frame cap in single player games. No point in letting the card work as hard as it can if you are okay with 90fps in a game where it would have gotten 120+. In those titles with the frame cap the 9070 may use less wattage than the 9060XT.