I'd argue kettles and toasters are not independent actors. A toaster won't make a decision if another toast is needed, it will not grab a slice of bread and then toast it.

But a roomba is really an independent actor and we already see problems with it (roomba companies collecting apartment layout data, pets feeling strong competition, people feeling rather helpless if a roomba doesn't clean some place or gets itself constantly stuck on rugs etc). Sure they are not big problems, but roombas aren't really big independent actors either.