I think the goalposts are solid but maybe there is some misunderstanding/disagreement of what's going on with the chipped physical keys vs fobs causing it to seem as if I must be trying to move them.
There were early generation keys for VATS/Pass-Key I/II style systems in the ~~80s-late 90s which weren't actually "chipped" but had some protection mechanisms mostly based around resistance. They were a bit useless in that they were very limited in possible values so even without a key one could just guess through them. Beyond that, there were also just cheap bypass modules https://www.the12volt.com/installbay/forum_posts.asp?tid=845.... Really, these were not much different than going after a normal physical key car because of the lack of actual chip. I don't think you were referring to these for these reasons, but I thought I'd cover them anyways.
Actual chipped-but-physically-inserted keys https://www.key4.com/gm-transponder-key-b111pt?srsltid=AfmBO... using chips like Hitag2 https://www.nxp.com/products/rfid-nfc/hitag-lf/hitag-2-trans... started to hit the market towards the late 90s. These still don't signal the chip communication through the metal of the key into the ignition though, they use 125 KHz RFID wireless transponders. The difference between these keys and fobs is, at most, the maximum range and they lack the buttons a fob would have. The underlying operation of the chip operate on the same principle though, there was no such thing as "wired"/"physically transmitted" chipped keys. As such cloning them was indeed as easy as buying some random RFID cloner and beaming it at someone's purse to then drive away. Of course the other attacks on the car systems themselves (i.e. without the key) also still exist but that's beside the point.
If you think you know of a chipped physically inserted key which you believe does not ultimately use an RFID transponder I'd be curious what make/model/year. Maybe there is just some key I've never heard of.
