It is indeed wrong to assume that the mere replacement of existing forms of human labor by machines will lead to technological unemployment, but if the technology driving that replacement is advancing at a rapid rate; if it is built on a technological infrastructure that allows for winner takes all markets; and if ultimately it could lead to the development of human-like androids, then there is indeed reason to think that technological unemployment could happen. Since this will lead to a significant restructuring of human society, we should think seriously about its implications.
Human-like androids are just a fantasy, there's no economical reason to build such unless for pure amusement. i.e. you won't see an army of androids sitting at the desks staring at monitors and typing on keyboards, you'll rather see a piece of software that can do the same at close to zero operating cost.
But human-like robots are good for the sake of discussion. Ultimately, if it is possible to develop robots who outperform humans both on physical and intellectual level, then the need for human-labour will almost entirely disappear.
Any sort of IA or human like robots aren't needed to get rid of most jobs today. The human-like robots will come handy when they automate services like hotel receptionist. In Japan there is an hotel that works with human-like robots only, imagine how many potential jobs got lost there and imagine when it goes worldwide.