Cyberpunk 2077 will for sure run on a GTX 970. Maybe at reduced settings but it should still be better than the base console version. If it can run on an old Xbox one base model then you can sure bet it will run on a GTX 970. Some games just will not run well on ultra or even high settings. All you'll be paying for if you get an RTX 2060 is a slight bump in level of detail or higher FPS which if you already get 60 fps it won't matter anyway. Sure... You could have a better card now for future proofing.... But which makes more sense? To get an RTX 2060 now and have an RTX 2060 or to save the money until you need a new graphics card and get something even better? If you can't save the money you have bigger problems and maybe you should focus on those bigger issues than to run out and spend. But hey.. If you think you need higher level of detail... If it means that much to you to max out a game or to play on high rather than medium then I'm not going to tell you you can't go buy whatever you want to achieve what you want. And I can't tell you how well an unreleased game is going to play. It may be locked to 30 fps for everyone. Some games are only meant to run at a certain frame rate.
The CPU you have won't bottleneck the cards you mention by any significant amount. I have a 4790K with a GTX 1080 ti. I can play 1440p high refresh rate or 4K 60hz on my TV. Get the RTX 2060 if you want it. As far as that goes get whatever you want. if you want an RTX 2080 ti and can afford it then by all means get it. You won't benefit from it at all but if it makes you feel better somehow to see higher fps on the fraps fps counter or msi afterburner(whatever you use) then that's perfectly fine. Like I said before... Upgrading to an RTX 2060 likely means only higher level of detail. If you really want something awesome get an RTX 2080 or GTX 1080 ti and upgrade to a 1440p high refresh rate panel... Or if you can't afford that a 1080p high refresh rate monitor with an RTX 2070.