MFi vs. Non-MFi accesories

sure,

as long as it's no higher than 5volts and the connector fits and it's minimum 5 watt then it can't harm your device

but these are international forums and some nations does not enforce regulations in terms of quality and safety of electronic equipment very much, MFi is a std. where apple verify the quality with their stamp, in my country I would trust that the CE mark would provide equally insurance of cables and ac chargers not being of a quality which could cause a hazard.

depend on the laws of your country and consumer protection really

where I live (europe) I would trust any cable and AC charger sold legally in the country

devices which were not quality and could harm devices would not be legal to sell in shops

(I used several supermarket cables and interchange between 230volt AC chargers from various manufacturers and from other devices, my ipad pro mostly charge from my oculus quest 2 (vr glasses) ac charger and cable)

but from what I can understand this does not hold true in all countries in the world