The ostensible benefit to DC distribution in homes is to be more economical and simpler for devices that already run on DC - not to redesign ever device ever made to accept mains-voltage DC. If your iPad and your laptop and your blender still need a power brick to work, what's the point?
Using high-voltage unnecessarily to avoid using a DC converter is also not going to save money. Yeah, you can use a 300 V DC motor in a coffee grinder, but why? It's just going to cost more money to make.
Using high-voltage unnecessarily to avoid using a DC converter is also not going to save money. Yeah, you can use a 300 V DC motor in a coffee grinder, but why? It's just going to cost more money to make.