People with newer macs keep telling me that Cubase is running great for them. I wish one of them would do a comparative test as I have done in order to find out for sure. I have a metal GPU and everything else on my mac increased performance substantially under Mojave...but Cubase10 just runs like a dog...and increasingly so with more tracks added, which means...its probably the DSP that is causing the problem more then anything. Move the DSP to VEP and it runs considerably better, though still not nearly as well as the other DAW's with VEP. We can only speculate what the problem with Cubase is, Steinberg has to be the one to figure that out.
If you want to use Cubase on a mac, my recommendation is absolutely use VEP. It can still be used for workflow reasons, just realize its going to use more CPU then the other offerings. But as long as you can play all the tracks you want to play and play with low enough latency..does it matter if the CPU is pegged to 60% vs 40%? Not really. I could not playback 90 tracks on my system without VEP, but with VEP it could play it..though using a lot more CPU..I don't know when and where it would max out... but it could still be perfectly usable if Cubase workflow is what you want and need! But I highly recommend you plan on using VEP with it.