It seems like people are assuming that all products are commoditisable from a market point of view, and from an industry point of view, which isn't true.
E.g. Just because watches are commoditisable from an industry point of view, in the sense that they can be manufactured en-masse for next to nothing, the buying behaviour by consumers for watches indicates that they can not be commoditised, because brand equity is a factor in purchasing, features of the watch are a factor for purchasing, etc, and therefore product differentiation stops them being a commodity.
On the other side, just because consumers would accept commoditised, mass produced, cutting edge CPUs, does not mean that industry can provide this. The barriers to entry for this industry prevent them from being commoditised (R&D costs, human resources, capital costs and so on)
So to look at what technologies may soon become commoditised, you need to analyse current and future demand, and current and future supply. You'd also need to analyse both the markets for the product, and industry groupings within the supply chain for that product. Some simple analyses might give you an idea, e.g. a proper Porters Forces analysis, consumer indices, technology trends, etc.
An interesting current example for me are 3d printers. Because the barrier to entry for designing and creating and selling a rudimentary 3d printer is so small, it has the potential to be commoditised. But from a marketing point of view, it probably can't, because it's a new technology and so brand differentiation might affect buying behaviour. From a consumer perspective, not enough people want or care about 3d printers, so in turn, suppliers wont churn them out. From an industrial point of view, it would be hard to create barriers to entry for new entrants to the market because it's not complicated to create a rudimentary one, so it's probably not a profitable venture for incumbents, and so on.
Another example would be the resurgence of VR. That's an interesting one because you can witness companies doing their best to create barriers to entry for new competitors, to avoid it being a more commoditised product, despite also being easy to create a rudimentary version (emphasis on 'rudimentary'!)
From a marketing fundamentals point of view though, commoditised products tend to be ones that are cheap to make, are consumed in some manner, and which consumers don't have a brand preference for, therefore buying the cheapest product available. E.g. screws, staples, but not, say, certain breakfast cereals (because people exhibit preferences for different brands of cereal and don't just buy the cheapest possible). Most new technologies can't fall within these parameters.