The Finder needs a slight adjustment to make items appear.

With the death of iTunes in macOS, Apple shunted access to connected iPhones and iPads to the Finder via the Locations section of the sidebar. Some readers reported not spotting their devices there, and had no idea how to get them to show up.
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https://www.macworld.com/article/3452519/macos-catalina-how-to-make-your-iphone-and-ipad-appear-on-the-desktop.html