Counter top dishwashers are still about in Europe. AEG among others have them.
Equator and later Danby began selling countertop dishwasher in USA a while ago. Now there are all sorts of cheap versions (nearly all made in China or at least Asia) including one by Farberware one must fill with water before using.
Countertop can openers seemed to be everywhere when one was growing up. Recall reading many consumer publications that basically called them gross because unlike hand held models some could not be washed thoroughly.
Thor's "Automagic" combo washing machine and dishwasher yes did come with a "yuck" factor to many housewives and others. However one had to purchase the dish part separate and many housewives really only wanted the washing machine, so.... This is one reason why tracking down those dishwasher tubs is difficult IIRC, Thor just didn't sell them in huge numbers.
Yes, spread of households with microwave ovens killed off demand for all sorts of other kitchen counter top appliances. Hot dog makers, popcorn makers and more became surplus to requirements.