So what do we learn from this:
1. A 30 megabyte blob of sourcecode + hardware dependent extensions probably contain lots of lots of bugs. Probably way more than the bit of assembler code in the BIOS.
2. Samsung doesn't have high quality standards, at least not when it comes to their own EFI extensions.
For me that means that for future hardware I will prefer one without EFI, because it will be buggy for the next 20 years. I also will try to avoid Samsung as they are likely to add more bugs and even critical bugs. (Although seriously, Samsung never has been on my radar for laptops, they never showed up anywhere where I was looking)
Now if I may gaze into the crystal ball to predict the following:
Eventually there will be bugs found which can brick the hardware just by a boot attempt from USB or an SD card. Since there's a service mode in modern CPUs the attack vector might even be USB at runtime or the managment mode of the Ethernet chip. (Intel offers extensive OS independent management over Ethernet with their chipsets)
This will even work for machines with "Secure" Boot enabled, making them somewhat less secure than their BIOS equivalents. Of course none of that will be patched. Some people will however still defend Secure Boot with their life, claiming that it's not just another vendor lock-in system to prevent Microsoft from completing with others.