Your right Im afraid.
Many new washing machines (and other white goods) use PCB’s and ‘Thyristors’ for ‘soft start’ motors and controlling other operations.
There are three main types of generator that you will come across:
1. AVR controlled – very good voltage/frequency control, tend to be on more expensive or heavier installed type generators
2. Capacitor controlled – not very good voltage/frequency control. Tend to be on cheaper generators, typically the type with a tubular frame around an open petrol engine.
3. Inverter generators – quite good voltage/frequency control, tend to be on smaller compact ‘handbag’ generators. Some useable some not.
It’s not easy, it is one of those things where what is a good arrangement for you may not suit someone else.