It's not all that different from many other electronics items these days, including the computers most of us use every day. There was a time not all that long ago when coders worked to make their code efficient and some would even say "elegant". Now we have bloated software for everything, since no one seems to think efficient and elegant code is necessary with all the relatively cheap memory and processing power available. If you want examples, consider the bloatware Microsoft puts out these days, or compare the earlier versions of Adobe Reader to the POS they distribute now.
It's a never ending process. New bloated software is developed, so new hardware is then developed to use the new software, then the software is further bloated so new hardware has to be developed, ad infinitum. It's how they keep people buying new stuff even though the old stuff really isn't old yet and works just fine. Ever heard of planned obsolescence? In the case of Garmin, the devices tend to last a long time so the best way to get you to buy new ones is to make it difficult or impossible to upgrade the old units. Then you have Apple. Buy an I-pod and they make sure you will have to buy another in a few years because the batteries are not user replaceable (not easily anyway). And of course these days the big thing is the "new and improved" smart phones that come out every six months to keep those who must always have the latest and supposedly greatest constantly standing in lines to pay way too much for another soon to be outdated piece of hardware.
Jerry