Possible Solution?
After experiencing this Philips SmartImage racing issue multiple times daily for three consecutive weeks, I made a configuration change that has stopped the issue for ~48 consecutive hours (and running, as of the time of this post). I wanted to wait at least two days before posting back here to make sure what I was seeing was real and not an artifact. On a whim, I opened the NVIDIA Control Panel and disabled G-Sync and rebooted and the problem immediately stopped. I rebooted several times since disabling G-Sync and the SmartImage racing issue has not recurred on my three Philips monitors.
I'm standoffish to call this a solution as I'm just grateful for being able to work for two whole days without this issue interrupting my work. I realize that I could easily enable G-Sync to test whether the issue comes back but to be honest, I'm scared to do that as I don't want to jeopardize this moment of peace.
Can a few other who are using NVIDIA cards and who are also suffering from this issue test to see if they have G-Sync enabled, and if so, try disabling G-Sync and report back as to whether or not the issue goes away? Fingers crossed!
UPDATE 5/3/2024
This solution did not work. Windows rebooted without my permission last night and installed another round of updates, and now the problem has started again even with G-Sync disabled. I uninstalled the unsanctioned new updates and rebooted 2x, but the issue persists.