Fuses are one time thermal overload/time current interrupter, they are fast (no mechanical delays).When fuses get older they get more sensitive to overcorrect, blow easier and become “ more “ safe. Circuit breakers wear down, parts rust, wear down, become stuck, circuit breakers get less dependable over time. There are DIN fuses with very high current interruption ratings over 100,000 Amps. There are no fuses for very high voltages above 20,000 volts. Fuses are failsafe and cheap. Also when a fuse is removed from the fuse holder, there a clear visual indication that the circuit has been disconnected and is safe to work on.