From what I experience, I think it's quite evident that that there is a decrease in cw activity because of coin reduction.

Also people are missing the main point. With the time investment you make, you are better off questing and rebirthing than cwing for coins which isn't what you want to do when you want to invest in the skill level of players so that clan wars will be more active ---> Attracting more competitive players ---> Increasing player count.