I checked, and I do have the 4GB file on my system.

The “Local AI” toggle is enabled. Chrome never asked for my consent to enable it.

Screenshot: https://imgur.com/a/S4WTHxM

The 4GB file is located in C:\Users\[user]\AppData\Local\Google\Chrome\User Data\OptGuideOnDeviceModel\2025.8.8.1141

Screenshot: https://imgur.com/a/wvTqfQM