Two issues for you, and I'm making these points based on you using the cards on Windows and for gaming.
One, the 1080 is more than fast enough, but nVidia *always* gimps their drivers on purpose for older cards. It's just a matter of when, not if.
The second issue, *everyone* has been running into fab-time scheduling delays well beyond whatever they expected in the past. Remember, this card was delayed more than normal, and nVidia's reasoning was, because they had no competition, but that is actually BS and only fanboys buy into that argument. The fact is every chip fab on earth has gone through enormous delays transitioning minor tech advantages(that still pay off, so its still worth it), but we are in that phase where physical reality hits walls to how quick we can adapt new tech. And no, this is beyond the Moores Law stuff(which hasn't been relevant since 1999 anyways, but laymen love to bring it up as if it's still relative to anything, to which it is not). So that means diminishing returns, yes, which is why a 980 to 1080 is not a big jump. Hype is hype, every new card is OMFG new great thing(BS, it's not, except on super rare occasions). But a 780 to a 1080... well of course that's an upgrade. But lets say you had a 980 (and let's say two years wait), you're not really in a hurry unless you have a hole in your wallet. So that 2080 on sale (600ish) will actually get you more use and value than a $350 1080 if you really think about it, strictly because you are on a 780 now, and that lines up better with your upgrade plan. Since a 1080 user will look to sell now or upgrade in 2 gens, a 2080 will be comfortable for 3 gens. That is strictly going off trends that gens are no longer 1 year apart, but many years.
Makes sense?
2013 (700 series)
2014 (next)
2016 (next)
2018 (now)
So 2020? Or Are you going to wait until 2022(maybe it will be 2023 by then?) for your next card(as a 1080 owner?) At this point, the extra for the 2080 (and yes, I don't mean MSRP, but one on a reasonable sale) makes a heck of a lot more sense for a 780 owner.
Hate saying wait... Especially when a 780 is still ok, but... wait, or find a sale on the 2080. The 1080 was great when on sale, but not many liked it when the prices were jacked. Same with this. Either go all-now, which means you're beta-testing a launch product. Or just wait until the hype cools down, and it will. Thus sales will happen, and things will be slightly reasonable. Not a long wait. You'll have your card by the time it's too cold to enjoy spending time outdoors.
