The Adobe Creative Suite is one great example of customizable UI. Because of the complexity and large number of commands needed for Indesign, Illustrator etc., Adobe gives you the user the ability to customize command menus and even preset common sets that are likely to be used in one workflow or production role. AI is heavily used behind the scenes in Photoshop and Premiere effects to help the user edit the photo/video. See Adobe Sensei…
A less complicated productivity software is Microsoft Office. All MS programs also allow you to customize toolbars and command menus. In the latest Office 365, AI has also been incorporated. For e.g., when you insert several photos into a slide in PowerPoint, a design suggestion panel pops up automatically to give you many templates for displaying the pics in a creative and aesthetically appealing manner. The suggestions vary based on your Master template style and the number and size of pics chosen. See below pic.
In terms of content display, Medium itself is one good example of an app that does this. On top of showing you content based on topics of interest you have indicated when you first sign up, it dynamically tracks everything you have read and adjusts your recommended articles in an area of your home page every time you go there next.
Netflix is another great example of an app with simple, intuitive UI and dynamic content serving based on the user’s latest content consumption. I also love how each image can ‘float up’ and auto play the preview trailer when you mouse over it. Almost zero lag!
Hope this helps.