Technology

Not for the reason you're thinking. DCDC conversion has gotten more efficient, but the problem is that nothing wants a specific voltage. Your LED strip might want 12 or 24 or 48V. Your phone wants 5V. Your single board computer might want 3.3V. Meanwhile, what's flying out of your solar panel array might be over 300V (depending on how they're wired together). You end up with layers of conversions that each take an efficiency hit. Add it all up, and it's better to convert the solar output to AC and then convert once to DC at the point of use. Which is exactly what we're doing.

Plus, items with larger draw, like a clothes dryer or electric stove, are going to want AC, anyway.

However, there's another thing that might make DC lines viable in houses. Power over Ethernet equipment has gotten relatively cheap. The base power levels are easily enough to run lights or charge a phone, and the more powerful versions can handle a laptop. What makes it especially interesting is that you don't need a licensed electrician to run it. You can't be a complete imbecile installing it, but don't need a license, either. That could dramatically reduce install costs in new homes. You need a proper electrician to install the breaker box and run a few high draw lines, but skip the rest.

As a bonus, any smart controlled devices no longer need wifi or zigbee or bluetooth or anything. They're already connected to the network by being plugged in.

PoE has been mostly an enterprise thing, but mass production for residential use should further bring prices down.