Many professional designers intentionally stick with the 2018 version. Newer is not always better, especially if you value stability and speed.

Support for OpenType variable fonts lets you customize weight, width, and slant using convenient sliders. Performance Benefits for Older Macs

Allowed natural distortion of vector graphics without manual path editing.

: Double-click the downloaded .dmg file to open it.

: Check the "Other Versions" section in your CC app settings.

Go to Illustrator > Preferences > Performance and ensure GPU Performance is checked. This leverages your Mac's graphics card for seamless zooming and panning.

Is your Mac powered by an or an Apple Silicon (M1/M2/M3) chip ? Share public link

To make Illustrator CC 2018 run "better" on your Mac, follow these technical best practices:

To get the 2018 version, you typically need an active Creative Cloud subscription. : Open the Creative Cloud Desktop App. Find Illustrator in your list of apps.