Also plenty of people who never who never were tested and *did* have COVID, but were assumed to have died because of something else. That argument goes both ways.
If someone who is terminally ill dies, but provably would not have died then if they hadn't caught COVID, what killed them? Sure, maybe the actual thing that killed them in the end their illness, but COVID was a direct factor in their death.
And yes, you can say without their terminal illness they would have survived COVID. That can also be true, but that doesn't mean it shouldn't be counted as a COVID death. If anything it just means 1 death is counted in 2 categories because both things alone would not have killed that person, but together they did.