It would be wrong to overlook these damages just because the ISIS leader is now dead. Yes, their main goal has now been achieved. However, the means to get to that goal caused a series of bloodshed, bereaved families, and fundamentally, left a country in terrible shape and condition.
Yes, the main leader is dead, but the teachings, the idealism, and the doctrine still remain
Furthermore, the death of the ISIS leader does not even guarantee the end of ISIS. Yes, the main leader is dead, but the teachings, the idealism, and the doctrine still remain. That in itself will never die, and as long as there are people out there who agree with this doctrine, IS will never truly be dead.
Despite the masses of bloodshed, it is important to know that ISIS did not only terrorise internationally; their own country too saw great terror. The fear that one of your relatives will suddenly want to join ISIS, ripping your family apart in the process, or the fear that your home could be blown up in the name of honour and integrity. Military intervention not only benefitted the rest of the world, but the inhabitants of the country too (obviously not completely, but to an extent).
This is definitely not a black and white argument, but the defeat of the IS leader sheds a light of hope, both internationally and locally. However, I do believe that the US and UK governments must help Iraq and Syria rebuild their countries, they are the ones that tore it down in the first place.
Joe Molander's take on intervention can be found here: https://www.thecourieronline.co.uk/the-long-game-should-we-have-intervened-over-isis/