Iwyze/Old Mutual expects their clients to pay 80% excess on a claim

I was involved in an accident where by a truck tyre burst on the highway and it hit the underneath of my car, it happened to damage the wheel bearing and the ABS sensor. I have never missed a single payment ever since signing up and this is the first time I claim from the insurance. A gentleman by the name of Scelo then called me back to give me feedback on the claim.

The total cost to fix is R9 000, excess is R3000(I am fine with this amount), however he then proceeded to tell me that because there is no third party I would have to pay an additional R4 000. bring the total to R7 000 which is virtually 80% of the cost. I explained to him that it makes sense to still claim from the insurance since when I need them I need to pay 80% so then what do they insure or why do I need them. The situation is them same as one driving around a farm and hitting an animal or a bridge falling on your car or any other situation which you don't have a third party and the insurance experts you to pay 80% of the total cost as excess. I am extremely disappointed in all of this since they are underwritten by old mutual of which you expect better service than this. This is my first claim with them and this is the level of service I get from them. I suspect the agents who deal on these cases improve their KPI's by rejecting as many claims as possible while every month expecting those same claimants to pay fully their premiums to the insurer. For a big corporation such as Old Mutual to expect their clients to pay 80% of their claim is frankly completely unacceptable to me.