CSGO is not a very demanding game. The GTX 1060 should have no problems running the game at 1440p and ultra settings. A GTX 980m is capable of pushing 230 FPS at 1080p and ultra settings; the GTX 980m is less powerful than the GTX 1060.
I have read the CSGO will be upgraded to use the Source 2 engine though. So when that happens I would expect lower performance in CSGO because while the Source 2 engine will make the graphics look prettier, it will also make the game more graphically demanding.
Dota 2 Reborn uses the Source 2 engine. The GTX 1060 manages to get 118 FPS at 1080p and ultra settings in that game. Playing Dota 2 Reborn at 1440p and ultra settings will naturally lower the performance...