Yeah you should be fine till 2020. Sadly you might face some bottlenecking due to threads,some i7 users already do but the number is very small, unlike i5 users which are many now. Games like The Witcher 3, The Division, Rise of the Tomb Raider use 8+ threads and others like BF1, Watch Dogs 2, Ghost Recon Wildlands, GTA V can use near 16+ threads. The number of games that use a lot of threads will only grow. On the up side there are a lot of 4C/8T Intel users out there so devs won't forget them. Besides worst case scenrio if it does start to bottleneck, turn up more of the grpahics settings and get a btter picture with less stress on the CPU. Until a bottleneck makes 60FPS (or what ever your accepted frame rate is), you'll be fine. Plus even though many of games use a lot of threads, for now, being parallel the more cores/threads you have the less work each one does (DX12 at least 11 less so). You CPU might work harder but it should be good enough a few more years. If you question a CPU bottleneck or what your CPU can do in games...
1. Turn down all in game settings to low and the lowest resolution.
2. Run game with fraps or frame counter...
3. what ever that number your CPU can achieve it always can (maybe more but not to much) at any resolution and game setting as long as your GPU is strong enough.
More times then not it is your GPU that is the limiting factor for <90hz/fps gaming. Jump tp 120/144 then your cpu is A weak point too, always for the higher refresh rates.