Dimension
AEMaaCS Traditional
Document-Based
Universal Editor
Authoring UI
AEM Sites page editor, component dialogs
Google Docs or Microsoft Word
Universal Editor — in-browser, in-context
Content storage
JCR / Apache Oak repository
Google Drive or SharePoint
JCR via AEM cloud
Delivery layer
AEM Dispatcher + CDN
Edge Delivery Services
Edge Delivery Services
Developer model
HTL templates + Sling components
Vanilla JS/CSS blocks, no framework
Vanilla JS/CSS blocks + UE instrumentation
Default Lighthouse score
Requires tuning to reach 100
100 out of the box
100 out of the box
Author learning curve
High — proprietary CMS UI
Low — familiar Office tools
Medium — custom editor, visual context
Live preview
In-editor preview panel
Sidekick extension in browser
In-canvas preview inside Universal Editor
Best suited for
Large enterprise portals, transactional apps, complex personalization
Marketing sites with existing Drive or SharePoint workflows
Marketing sites needing rich visual authoring without document constraints