I had the same problem, with an electronic switch, not even a dimmer, I was using G9 bulbs, which are rather small, the size has to be small so the glass covers fit, OK glass covers were for the quartz version of the bulb to stop harmful rays and hot bits landing on the floor if they explode, but the chandelier clearly designed to have covers and looks very different without them.
So originally using small bulb to right, then wife got 5 of the bulbs on the left, no flicker, but within 24 hours one had failed, ordered replacement and opened the failed bulb to see what was in side, the smoothing capacitor was nearly as big as the whole of the other bulb. Also found fault and corrected and still working today a year on.
However just one quartz bulb and four LED bulbs (small) and it also stopped flickering, there is clearly an incompatibility issue rather than saying either the switch or bulb at fault, the bulbs worked fine without an electronic switch, and the switch worked fine with other bulbs.
The larger G9 bulbs do have a higher output, although not legal to sell in this country as no watts or lumen marked on bulb or package, and the switch says bulbs should be 5 watt minimum, I had assumed this was a total, but maybe it means per bulb? So the problem could have simply been too low of a load.
So if a switch says "Min. Dimmable Load (LED) 5 W" and "Min. Dimmable Load (Incandescent) 10 W" as the
screwfix LAP dimmer says, then at 50% you need 10 watt or 20 watt bulbs. Remember min load is when dimmed. At 20% would need a 25 watt load, only my living room with 8 x 6 watt would have enough load when fully dimmed.
In the main I have moved to smart bulbs, I got a 3 x GU10 light bar from Lidi with a remote control zigbee, the remote is used for other zigbee bulbs, and the GU10 are in my bedroom, plus one BA22d or when I dim bulbs the smart switch has not got enough load. The bulb revert to full output once switched off, but not only can I dim bulbs but can also alter the colour temperature so they have some ambiance.
If there is a neutral at the switch then maybe the dimming switches which use the neutral would be better, not tried as no neutrals at my switches, living room use cabinet lights to give ambiance, as 8 x smart bulbs rather expensive, but else where I simply use smart bulbs, simply not worth the hassle working out what bulb will work with which dimmer.
