My understanding is that for anything big like a fridge (even a minifridge) the efficiency and reliability of standard well-optimized 120V AC appliances means it's worth it inverting to AC instead of sticking to DC. Lots of RVs use/used 12V DC systems so things are available, they're just not very good. Inverters are very efficient these days. Plus it's really helpful to have a way to run AC things you already have if you need to.
Though if you only want lights, I do see how DC could make more sense if you can either find or DIY the right electronics to handle the voltage issues.
My understanding is that for anything big like a fridge (even a minifridge) the efficiency and reliability of standard well-optimized 120V AC appliances means it's worth it inverting to AC instead of sticking to DC. Lots of RVs use/used 12V DC systems so things are available, they're just not very good. Inverters are very efficient these days. Plus it's really helpful to have a way to run AC things you already have if you need to.
Though if you only want lights, I do see how DC could make more sense if you can either find or DIY the right electronics to handle the voltage issues.