Intermittent software lags and slowdowns

The bug is a seemingly random and intermittent brush lag on a Mac M4. It persists after all troubleshooting procedures (versions 27.9.1 and 27.10)

Product: Adobe Photoshop
Versions tested: 27.10 (current),  27.9.1 — identical issue on both, 26.0 and Beta
System: Apple Silicon M4, macOS (latest version), 24 GB unified memory
Since: The issue first appeared roughly on the latest version

Random slowdowns occur while drawing or erasing brush strokes in Photoshop. The stuttering happens unpredictably, with no discernible pattern, and delays and groups every action made during the freeze at the end of it. Tool changes and windows also freeze. The document involved is not large and the issue is reproducible.

Causes ruled out through diagnosis:

• The issue persists in all of the following configurations, which eliminates each of these as a cause:
  •⁠  ⁠Rollback to version 27.9.1 (identical lag)
  •⁠  ⁠Full reinstall of the latest version with preference deletion
  •⁠  ⁠New standard macOS user account (identical lag)
  •⁠  ⁠OpenCL disabled in advanced graphics processor settings
  •⁠  ⁠30-bit display disabled
  •⁠  ⁠History kept to a normal amount
  •⁠  ⁠Testing with the built-in trackpad (no external tablet or graphics peripheral involved)
  •⁠  ⁠No external display — internal screen only
  •⁠  ⁠Machine otherwise healthy: no stuttering in Preview.app or other applications; drawing tests outside Photoshop are smooth. Disks have plenty of free space.

Additional tests performed with no effect:
•⁠  ⁠RAM allocation set to 75–80%, cache levels to 4, cache tile size to 1024K
•⁠  ⁠Brush spacing checked (set to 1%) and smoothing checked (set to 0)
•⁠  ⁠Adobe Desktop Service / CCXProcess processes terminated and tested immediately after
•⁠  ⁠Verified absence of obsolete options in Technology Previews

The issue has only been fixed by trying to replicate the issue on another machine, but for the Mac which is my main workstation, I have ran out of ideas to fix the problem.