Is the 1070 basically a 980 or a 980ti? Those are two entirely different cards in two separate performance tiers.
Of course the answer is the 980ti, though in reality the 1070 easily beats it at stock clocks. The 980ti is a beast OCer so if you want to OC then the 980ti is likely the better choice.
What you're alleging is that the argument is that because there's a comparable card the 480 is pointless, but that's not the argument. Yes, there was a comparable card for the 1070 on release. The reason the 1070 was anticipated is because that comparable card cost twice as much as Nvidia told us the 1070 would cost.
The 1070 was MSRP 370 dollars while the 980ti was 670 dollars. For some reason, expecting a 370 card to beat a 670 one from the previous generation was perfectly reasonable, but expecting a ~225 dollar card to beat a 400 dollar card from last generation is ridiculous? Typically we expect newer cards to perform better as technology advances and graphical demands increase. The only thing new or ridiculous here is the notion that a midrange card replacing previous gen midrange cards is the norm. A die shrink especially is where we should see major performance gains for less cost.
Not to you specifically but this is also why the car analogy I saw earlier is ridiculous. You can't equate an industry where units from over 30 years ago are still just as viable as the brand new ones. Technology industries rely on increasing performance for at very least comparable prices. The status quo is a failure in the tech market.