Hisense dishwasher rusting racks

I bought a Hisense dishwasher in 2020, and all the racks in the dishwasher are rusting on every joint, and the dividers are falling off after every wash due to rust.

Upon reporting this to Hisense I was informed that it is no longer covered due to it not being covered by the expired warranty. Does that mean I will have to buy a new dishwasher every 4 years due to the rusting racks, and that it is normal for racks to rust? New racks will be more than R2500 for the 2 racks.

I am leaving the dishwasher open after every wash for it to be able to get dry after the wash. Even this measure does not prevent the rusting of the racks.

This is unacceptable, is it then normal that every dishwasher that I am going to buy that the racks is going to rust?

My mother is still using the same dishwasher for over 15 years without a single defect or any rusting. (not a Hisense)