Thanks for all the replies.
There is an idea that appears highly questionable to me:
It's possible to make a PCB that will support ANSI, ISO, JIS and hybrid layouts from the same design, due to these layouts all using the same basic stagger. This allows economies of scale that would not be possible with non-staggered layouts, as the market is small and it would require a completely new design, rather than a small modification of an existing design.
It can be done, but it is actually done? Could you show some evidence for this?. Where do you get the idea that this is the case?. It is not harder to move 5 contact pads than to move 100 to make a new PCB design; this is done only once in CAD software and replicated thousands of times with modern automatic manufacturing methods.
I have good reasons to think the contrary: PCBs are highly non-standardized. We all know of trivial variations among mainstream keyboards that would preclude or make harder to use standardized PCB designs, like embedded arrow keys in the main key block, keyboards with split backspace, multimedia buttons, function keys in non-standard positions, and so on. All times I have dissembled a keyboard, I have seen a perfectly fitting PCB without extra unused contact pads or traces routed to unused locations, thus almost surely non-standard but instead tailored (possibly to a small family of keyboard models, not necessarily a single one).
PCBs can't be the reason of why there aren't non-staggered keyboards: If manufacturers can make non-standard PCBs for ergonomic keyboards (of the type that are found in common computer hardware stores, rather than specialty keyboards) which feature a curved design or the main key block split into 2, then they can also make PCBs for non-staggered keyboards.
I gave such an example in my previous post -- the QFR PCB. Here's a picture (not mine, but from elsewhere on GH):
If you take a look, you can see provision for split backspace, ISO enter, split right shift, and JIS bottom row. It isn't visible in that picture, but there is also provision for split right shift on those PCBs; the same design could be used to do ANSI, ISO, or JIS boards. From a manufacturing standpoint, this means that their PCB fab can just crank out the same design all day long, and it can be used to build multiple boards. This is possible because there are very few points of overlap between the ANSI, ISO, JIS mount points.
To be able to create a PCB that could be used for non-staggered boards, a different design would need to be used. It would potentially impact the structural integrity of the PCB and almost certainly overly complicate the layout to try and get a single PCB design that could do staggered and non-staggered layouts.
Consider that all the time a factory spends retooling to make a non-staggered PCB (and retooling back to original production, if necessary), as well as the time they actually spend manufacturing said PCBs, is time that they are not making PCBs that satisfy the primary consumer demand. For a large production run, the retooling time is a smaller fraction of the overall time used, but for a small production run, the retooling time can be a significant fraction. For the factory to maintain its profit, smaller runs of PCBs will be more expensive (same economies of scale that we see with a lot of GBs).
This same logic illustrates why board manufacturers might like to standardize PCB layouts where possible -- it is cheaper to order one run of 2
n boards that can be used to make both ANSI and ISO, for instance, than it is to order two runs of
n boards each, one for ANSI and one for ISO. However, the increased complexity of design required to make a multi-purpose PCB might increase the cost of the design by enough that a company would not find it worthwhile for the reduction in production cost.
At this point though, I feel like we are swapping anecdotes and not really forming an argument. Looking more critically at your post, I think your experience of "common computer hardware store" keyboards is limited to cheap rubber domes and the like, (or at least those boards are the ones you are attempting to ask about,) whereas I have been able to try razer, corsair, CM, logitech mech boards in several local stores, and am mainly working with the latter group of consumer mechanical boards. As I stated in my original post, I have no knowledge of the manufacturing process for rubber dome boards, and could easily be entirely off base in that field. However, I would expect that lack of demand for non-staggered boards plays a significant role in companies evaluating the cost/benefit of offering such a board.
I feel like I should state that I'm just hypothesizing based on an incomplete set of observations, hence the use of a lot of "possibly" or "I would expect". It may not be right, but it seems at least logical and internally consistent to me.
