I have the exact opposite of what others said. I just bought a new 6 core Mac mini yesterday and I am having unusable performance with Cubase 10. Glitches and pops and terrible timing with far less tracks and plugins than my 2013 2 core iMac that died yesterday.
All the audio/midi hardware is the same, and changing the buffer of the audio interface lower or higher doesn’t help. The performance meter runs about half way with 2 instrument, 8 audio, 2 midi tracks, and 6 plugins.
It’s disheartening, and I can only think it is either/all cubase, Mojave’s, or the focusrite driver.