Laundry repair costs a lot around here. Repair people certainly put a value on their time. It does take a while to get the machines apart and back together, but if you have a good idea of the part that needs replacing, it's not too bad to do many things.
Repair service will replace the subassembly that has failed. In TFA that would be the entire transmission. Very few would disassemble it further to replace only the actual failed part. And if they would, that's hours more labor.
So you're paying for a new transmission, plus labor and service call fee. This easily could exceed the value of the washer, and certainly would have many people thinking "Eh, it's 15 years old, I'll just replace the whole washer."