I’ve just downloaded and tried Sketchup 2019, specifically Layout 2019, to see if it fixes the zooming issue that I suffer with on a powerful new iMac with OS Mojave.
Disappointingly, it makes no difference. Still unbearably slow, laggy, jumpy zooming. Makes no difference where the Scroll wheel preference is set.
Anyway, I’d be interested to hear if any other Mac users, using Sketchup under OS Mojave, experiece this.
At the moment it is 2018 for me, with Layout on my 2015 MacBook Pro, under High Sierra.