It will take more time to develop such computer. For now it could be consider as fiction like the earlier scientist where they predicted the invention of flying vehicles and even they were called as crazy before thinking of such impossible to happen. But it did and airplane was being invented. Now in regards to quantum computer, it will be complicated and will going to require devices compressed already to a minimal size with powerful designs of circuits that will going to run as quantum computer.
Kind of I guess. Quantum computers definitely are possible, and have been made just not at the required power to be able to effect current standard algorithms. A quantum computer isn't very likely to be compressed any time soon, it might not even be physically possible, because of the amount of power that it requires, it needs to be cooled effectively. If you compress the machine too much, then that defeats the point. It would probably require operating in a sub zero room for it to be efficient also.