Older Macs running macOS Sierra or High Sierra may not support the latest version of Illustrator.
If you need to get Illustrator v21.0.0 running stably without crashing, use the following structural system modifications. Step 1: Force Rosetta 2 Execution (Apple Silicon Macs) adobe illustrator cc 2017 2100 mac os patched
Some of the key features of Adobe Illustrator CC 2017 21.0.0 include: Older Macs running macOS Sierra or High Sierra