Is macOS 27 exposing Swift Concurrency problems that Swift Evolution should address?

macOS 27 has had, and still has, quite a few strange UI glitches and moments of sluggishness, even on fast Apple Silicon Macs. Given how much UI behavior changed and broke during the beta cycle, I suspect Apple may have reworked a significant amount of the UI using Swift and Swift Concurrency. Could some of the remaining sluggishness be caused by priority inversion or other concurrency problems, where UI work gets delayed even though the machine has plenty of performance available? If macOS 2...