Moderator closed Zwift on MAC high CPU (ping @Andrew_Jones) so I guess I have to reply here instead. High CPU use on Macbooks has nothing to do with Makuri/Neokyo, it has been like that since always, there is some kind of not quite overclocking going on as long as you are operating with a power adapter connected. The game is rendering normal scenery already in the background for the start menu screen so that’s why the load goes up before you even start riding yourself.
For what it’s worth, I suspect that the thermal load from less than ~6 months of Zwift use damaged the screen in my Macbook Pro (first as thin horizontal stripes only visible with certain colours which later developed to a completely borken display) so continue at your own risk.