The reason Wouxun does not offer firmware updates for these models is simply because the firmware is not user upgradeable. Would it be easier to introduce changes to the radio using firmware updates? It depends somewhat on what the changes are and how they will be implemented internally.
In some cases, such in the case of the KG-1000G, certain firmware updates are not possible because the hardware itself doesn’t natively support them, and it would require a hardware modification to make it happen, which would require the radio to go through FCC recertification, which can be an expensive proposition. There is always the possibility that Wouxun may offer such upgradeability in future models, but that’s really their call.
It is important to note that not all radios on the market are firmware upgradeable by the end user, particularly those that are hardware rather than software driven. The firmware is only as malleable as the circuitry allows.
As an old school IT guy, from my personal perspective, updating firmware in components can be a tricky thing, and if not done correctly, can cause more issues than it solves.
It can be especially problematic from a support perspective. Not to get into the weeds on that one, but in a nutshell, it can be rather resource intensive and a huge time suck for tech support to untangle situations with “bricked” radios due to failed or improperly executed firmware updates. I know, I’ve lived it.
So, while I certainly understand your argument for firmware upgradeability as someone who uses the products myself, I also understand why some manufacturers may be hesitant to make it so. It’s not so much a matter of making money from newer versions of the same radio, it’s really more about the feasibility of getting a reliable and stable product to market for the long term.