When creating FILE > New… the 'New Document' pop-up appears immediately, but it's blank and the content/fields don't display for a good 7-8 seconds later.

I expect this to be visible immediately. I know there was a similar issue in Photoshop CC that you could avoid by using a legacy New Doc preferences.

Illustrator CC 23.0.2 on Mojave OSX 10.14.5