This how I look at it. The 3070 seems like a crazy deal but doesn't seem like a real jump. 3080 seems like a real jump and it's reasonably(relatively speaking lol) priced. The 3090 isn't as ridiculous as the Titan was in terms of why would you pay for that but it's pretty close.
The 3070 is a good deal, I'm told dumb ass people like @itsyoung he was wasting his money on the super, which is basically just a 1080ti, the 3070 is going to be cheaper than that card when it was first released and more powerful than the 2080ti, everybody knew the 2000 series was a terrible buy. The 1080ti was a good buy because it will just now get leaped frogged this year, and thats only 3 years of dominance, but for 3 years you could get the most of the current gen games with that card, so it was a good deal and if you stuck with that card upgrading to a 3070 isn't that bad but the 3080 is the same price the 1080ti was when I brought, I sold my 1080ti for 450 few months ago because I was just going to wait on the 3080,people still selling 1080ti brand new for 700 on ebay they never gonna get that sale now and gonna have to sell a brand new card for dirt cheap, next month.
The 3090 is the best value, because you will be good for the next 8 years, its better to buy the best cards when the first release so you get the most out of them and don't have to upgrade every 3 years to get the best performance