Watchdogs 2 also runs surprisingly well on FX cpus, as seen in that benchmark. But one has to be careful with console ports anyway, Batman Arkham City for example would paint a very strange picture of PC performance (the port was and is a disaster)

But there are other valid examples, like Battlefield 1 in multiplayer. The 4 core era will end, and consoles might make that happen faster, but especially for 4K gaming I would not worry yet. Till gpus are fast enough to make cpu the bottleneck in those there will be a few more cpu generations to come. At least based on current performance and how gpus normally develop. We only just reached 60 FPS on high settings there, and that with the most expensive consumer gpu available.

But on 1080p and 1440p, that's a different story. Being more future proof for that development is one of the appeals of the Ryzen 5 1600 (6c/12t).

It's already ended. I have an 8-"core" AMD FX CPU, and I decided to underclock it to 1GHz to see how games reacted. You'd be surprised how playable many games are. Mostly, I guess, because the thread communicating with the GPU does not need all that much power, so frame rates stay semi-playable.

Anyway, with an underclocked 1GHz FX 8350, The Witcher 3 saturates about 5 cores in cities and nibbles on the sixth core. Dragon Age: Inquisition uses up to 8 cores. RiME uses 4 cores. TrackMania Nations uses 1-2 cores.

Generally, AAA games have been post-quad-core for years now.

I'd say it's already all but at an end. The Witcher 3 is probably the most intensive game I currently own. On my CPU (i7-4790k, 4 core/8 thread) standing still in a crowded city environment shows about 50% load across all 8 HT cores. Once you start running through the city use across all cores rises to a steady 60-70% with regular (every 2-3 seconds) spikes to 90+% on all cores. That's a two year old game. I have a feeling that when the next big wave of major AAA titles starts to hit, many of them will be severely limited by 4 core/4thread.