My two cents here
Is it possible for a 5V power supply to have very low internal resistance such that a device that operates at 5V turns down its resistance in attempt to draw 5A from the power supply , but instead accidentally draws greater than > 5A due to the power supply having very low internal resistance or being “too powerful” ?
Assuming power supply can provide voltage of 5V (10A)... If the current drawn by load (6A, accidentally) is less than the current supported by the power supply, power supply will be just fine. If the current drawn accidentally is more than 10A (max. Supported by the power supply) Power supply will either detect that and trips, or drops the output voltage to zero or may get damaged.
Power supply's current output is completely dictated by the load as long as load is drawing the current which is with in the power supply limits.
So if the load's operating voltage and current are within the specs of power supply it will be a safe working setup.
Can a power supply be too powerful for a device
Yes. For an example.. If power supply can supply up to 30 A and we are using a small Motor and an arduino.. Due to some accident if we do short then it can fry the parts..too powerful
PTCs are some examples which can be used to limit the current inrush, in case if it helps.