The first quantum computers were built using big chamber containing gaseous substance whose single atoms where the basic "engine", each one a Qbit. Since those first times the challenge has been to use more atoms, that is to have more Qbits and to be able to perform operations on these Qbits. Although in theory we know a lot on quantum computation, manufacturing a system that can work as a quantum computer has been baffling.
There are a few implementations, even commercial ones like D-Wave, that can be used as quantum computers but they are still not the "real thing".
Technology has progressed significantly, solving one problem at a time, but usually discovering that once a problem has been solved another one popped up. This is why after several decades of research on quantum computers we still are looking for it. As an example we are now able to create Qbits in silicon, in a chip, rather than in a gaseous environment and this clearly makes for easier manufacturing.
Here is a news coming from Australia, the University of New South Wales and university of Melbourne, reporting of a new 3D architecture for a chip able to maintain the coherence as Qbits are processed.
In spite of all progress made, a crucial issue remains the de-coherence affecting Qbits, in plan words the fact that errors pop in during the computation in a random way. It is like you have a transistor storing a bit (and processing it) that once in a while "gets it wrong". Clearly that would invalidate the all computation. In classical computers this may happen but it is very rare and there are ways to detect errors and to correct them.
In quantum computers errors creep in much more frequently and researchers are trying to find ways for correcting them. The architecture developed by the Australian researchers provides, as they claim, a firmer base for error correction.
For sure their approach is exploiting current chip manufacturing techniques and as such promises to deliver real products. But, as I said, once a problem is solved so far we have seen another one popping out. So, I wouldn't bet that this is the end of the quest for a quantum computer.