The trashcan Mac Pro desktop was heavily promoted to tech journalists before release to try and keep pro users from abandoning Apple. IPads and iPhones were going gangbusters then, and Apple had gone a long time without refreshing the Mac Pro. The common sentiment was Apple no longer cared about professionals that required workstation-level performance. IIRC, this was in the aftermath of the release of a neutered Final Cut Pro which seemed to cater more to prosumers than pros, since it removed key features.
The intention was to signal pros to hang in there, and then the trashcan got released and had perf issues with throttling due to thermal challenges. Good times.