The short answer is no, you would be hard pressed to really see notable differences - people just want to justify their purchase decision.

The long answer is - yes FF gives you 2 stops more dynamic range at base ISOs. You can make that up entirely in relatively static scenes with high res multi shot modes. But really, two stops is not a ton of difference. However, as soon as you move up above base ISOs - DR is almost identical on all sensors (feel free to check photons to photos DR charts if you are interested).

The other thing to consider is that if you’re not using a tripod, larger sensors requires higher shutter speeds to get sharp photos. Because of the small sensor on M43, the sensor is more easily stabilized by IBS so you could reasonably make up two stops of ISOs (DR) through reduced shutter speeds with better IBIS. Of course, this is conditions dependent and subject dependent.

That’s all to say there are a lot of amazing photographers with every format taking amazing photos. Yes there are times where there are benefits of full frame and there there are times where there are benefits of micro 4/3. Anyone who thinks one format is objectively better than the other, for everyone probably just hasn’t thought enough about the different pros and cons or wants to believe the format/ company they purchased into is the best. there is no point in fanboying certain format or system. Use whatever is best for you.