Edit: Personally, and I know I am in the minority, but there are currently zero DX 12 games that I am anticipating being interested in.
Maybe you think that today, but it seems obvious you are somewhat interested in keeping GPUs for a long time as the 7770 came out in early 2012. If you (or anyone) plans to keep your next GPU another four years that means upgrading in 2020. It stands to reason that by 2020 you might want a 2016 game or a 2017 game or two (then on sale) to play. There is a good chance the 2017 game will be a Directx 12 game, which means the 480 would be a much better option than the GTX 970 for playing that 2017 game.
The irony of budget gamers is many don't change their cards as often at the $400+ card folks that seem to switch out every time a new flagship pops up. We see countless people on here milking sub-$200 dollars cards like 7950s or 7850s or GTX 660s for way longer than any of the "enthusiasts" bothered to keep that 780 ti or Titan OG that aged poorly. Therefore in a counterintuitive way budget gamers should care less about the "now" than flagship card gamers because almost by definition they don't want to spend a lot of money on GPUs. The ultimate utility of the budget card over time determines how quickly you are
forced to spend more money for acceptable performance, which is a completely different motivation than the benchmark dog whistle that sells halo cards.
This is especially true when comparing the GTX 970 and the AMD 480 because both cards do more than well enough currently in games in 1080p as long as you are willing to tweak down a setting or two to get solid 60fps (unlike most the benchmarks we are seeing in the thread that push the cards to max to get to sub 60 framerates on both). So then you pretty much HAVE TO take long term considerations into account, and given our evidence so far that choice seems clear.
The GTX 970 does better with a weak CPU today, but it needs driver optimizations to keep its memory from being an issue (which we assume it will get less of as time goes on) and it absolutely bombs compared not only to AMD cards but even the 980 in every single Directx 12 benchmark we have. Meanwhile the 480 is behind in CPU optimization today, but it will get the full console effect from the PS4 Neo and in Directx 12 games it will be far better than a GTX 970 especially when we consider that Directx 12 alleviates some of the driver CPU bottleneck issue by design. Given this it makes no sense to even think about recommending a GTX 970 to budget gamers even they will never upgrade the CPU.
If you are spending less money then you have less money to waste on bad decisions, which is the kind of decision a budget gamer would make if they prioritize Directx 11 2015 titles that are in front of us currently. Directx 12 is the future that must be accounted for unless you are giving up on gaming, eventually there will be some Directx 12 game you will want to play even if all the current ones don't raise interest.