The problem with waiting is that if you would not wait you could use the better PC way earlier.
Maybe the new CPU worths the wait but it probably won't. Little extra speed for little extra money over current CPUs. And they always talk about new technologies to lure in buyers.
Well that much is true, i spend 10 quality years with the i7 920 ( and 2 gpu's ) spending around 700 euro's on cpu and board. I did not always linger on the forefront of tripple A gaming but i did follow games extensively. In the end it was Andromeda and Warhammer 2 that made me decide to get a new cpu, first a xeon and somewhat later the ryzen.
Point being is you can be more then happy with buying intels last 2 gen's ( 8 & 9 ) atm and be sure to have a lot of fun out of it.
While Ryzen did a lot of improvements between their zen and zen 2 cpu's, especially on the gaming plane, if you choose the right cpu it probably won't matter a lot. Don't forget most reviews and tests only mention the upper echelon gains while most perform exactly the same on vsync'd ( 60 hz that is ) systems
Still if you have the money and a release is almost near you are probably better served with getting the next gen version then the older ones