Zwift on Mac high CPU - 2.0

I’ve opened Zwift on my laptop, spec as follows;
MacBook Pro (15-inch, 2019)
Processor 2.6 GHz 6-Core Intel Core i7
Memory 32 GB 2400 MHz DDR4
Graphics Radeon Pro 555X 4 GB
Intel UHD Graphics 630 1536 MB
OS Big Sur

I haven’t even started a ride yet and Zwift is sitting at 55% CPU and all the fans are going full gas, has been for about 10 minutes, I must be doing something wrong, there is no way Zwift should be using that much CPU?

I originally asked in post Zwift on Mac high CPU / 564351 but the answer I got was not relevant as it happens in all worlds and has been going on since before the last update, I don’t know why someone decided to close it.

Even if you did not start a ride, Zwift is already rendering in the background. It’s the same on my windows machine where I can see load (nearly the same as when ingame) when I’m still in the menu.

And it’s totally normal that the Intel MacBooks start their fans if there is a little CPU/GPU load. Gets worse if you have an external monitor attached. Some on mine 2019 16“. Will be replaced with a M1 machine because of the annoying fans.

(Mac, not MAC)