I guess my intent was not to point out that it has a mechanical key, rather that the description of the key on the webpage was wrong (it is not hinged).
The mechanical key fallback pattern is standard across the industry for sure.
Article says key fobs are the same across all their cars and this looks the same as mine for a Sealion 5, there is no hinge for the key you just pull it out.
Likely the article authors just assumed from looking at the scan, if they’d actually tried to remove the key they would have realised their mistake.
Before keyless became defacto standard, most keys were fixed on a hinge - you'd first unlock your car by pressing a button on the fob, then swing the key open and use it to start the car.
Nowadays the physical key is only a backup, safely stowed inside the fob. It is meant to be pulled out only in an emergency.
Mercedes changed to the IR key in maybe turn of the 90's. The plastic blob would be used to turn the ignition like before, but the locking part was electrical (optical). There was still a metal key that could be pulled out and used on the exterior locks if the central locking was out.
When keyless start came, there was a dummy button that fit in the ignition lock that could be pushed to start. If there was a problem, you could pop it out and use the key as before.
IIRC, all that, so may have mistakes. Just crossed my mind that they went a few decades between no metal ignition key and keyless. MB being MB, I wouldn't be surprised if they still had models with that same "old" system and keyless as an option.
Yes sadly the Hyundai and Kia key fobs of EVs (at least EV9) don’t have the mechanical backup key in the fob anymore. So you need to carry it on your keychain. Don’t leave it in your trunk. If the 12V battery does out you won’t be able to get into the car.
Anecdotally on my Hyundai ionic hybrid from 2018 it does have a mechanical key in the fob, but it is very non-obvious. It’s physically the same piece as the keyring section at the top of the fob. There is a small catch you release to remove the key from the plastic fob body and it slides out the top.
All this to say Hyundai certainly knows how to do this. If they didn’t do it, it is almost certainly a deliberate omission.
The mechanical key fallback pattern is standard across the industry for sure.