Why do appliance repairs cost as much as a new appliances?

Repairing appliances takes expertise, time, and replacement parts. Most of the repair bill will be the labor component. A trained appliance technician can charge over $75 an hour. You are also paying for someone to drive to your home which costs both time and gas.
In countries where salaries are low, repairing things is much cheaper. It is much cheaper for a worker to be manufacturing a lot of appliances, then to have a repairman looking at just one. In addition, a lot of manufacturing employees are low skilled and work in countries where labor is cheap.
Economies of scale in manufacturing lead to an optimized production and delivery process. These factories are also heavily automated. Also, factories are purchasing parts in bulk and are getting wholesale prices. Therefore, it is not the repair that is expensive in so much as is the manufacturing that is unbelievably cheap.
Additional Notes:
Factories practice “Just in Time” manufacturing whereby products are produced to meet demand, not for surplus to sit on a shelf or in advance of anticipated demand. During COVID19, some manufacturers recalled branded repair parts from supply houses so they could be used to manufacture new equipment. With the replacement parts gone from supply houses, the wait for these parts would often be two or three times the wait for a new appliance.