Yeah, but no one is obliged to acquire the whole set that includes those two steel plates. User is free to buy only single hardware wallet ( too expensive for me though) and use the well-behaved method of storing SEED phrase on stainless washers as following all recommendations described
in this threat. 
Sure, but why would anyone give people less secure option with single point of failure anyway, even if it's only optional?
You know for sure that someone will use this since it is available, and most people don't really care about better security until some disasters happens, and than they can blame everyone else.
BTW, those plates are for the storing BIP 32 root seed (= NGRAVE "Perfect Key") rather than for the SEED phrase. If user will chose to create wallet with BIP 39 SEED phrase then those plates are useless and he will search for alternative way. I think they should add and highlight this in the description of GRAPHENE (= set of those two plates) product.