I'll start with I disagree that 100% CPU load during gaming is "cpu bottleneck." If folk want to define this as such, then from now on the only acceptable CPU could be the new i9 line.
I've seen 100% for years as games take everything we throw at them. Newer games seem to be worse about this than before.
I have i7 7700 3.6ghz rog strix 1070 ti 16 ram rog strix z270h motherboard and lately my cpu started to go to 100% when gaming, i never had such thing before, it started with going to 90 at first and now when i play such games as battlefield call of duty or other new games it is just stuck at 100% and wont come down unless i lock fps to 30 or in some games to 60, i would consider this as cpu bottleneck but i never experienced this before its something that started lately, i took my pc for troubleshooting to different places but none could find what the problem is.