LED trims just started flickering

[iustacould]

Solid state dimmers accomplish their job by “flickering” at a slower speed to give you the appearance of dimming. Since the issue is that your are seeing this on its dimmed setting I would remove the faceplates and adjust the “low end” dial or slide on the left side near the bottom of the face of the device. If it doesn’t have this tuner, per lutron, it is not LED compatible. See attached picture

 

[Flicker Index]

Components, especially the main capacitor can degrade in LED ballasts. Have you tried a different lamp?
If you don't already have one, buy this: https://www.lutron.com/en-US/Produc...ers-Switches/CredenzaLampDimmer/Overview.aspx it's useful for all kinds of troubleshooting stuff.

 

[WasGSOHM]

Solid state dimmers accomplish their job by “flickering” at a slower speed to give you the appearance of dimming.

This depends on a filament having a large enough thermal inertia. LEDs probably respond in microseconds.
Above 30 Hz, persistence of vision helps smooth out the variations.