If you are on an older version of macOS (like Big Sur) where the latest iMovie from the App Store won't download, the is the recommended version for stability. However, for those with newer hardware, PCMag suggests updating to the latest version to access 360-degree footage support and better motion tracking. iMovie - Ratings & Reviews - App Store - Apple
Before we dive into the technicalities of the DMG file, let’s look at why this version remains popular: imovie 10.3.3 dmg