Sodium chlorite is much more versatile than hydrogen peroxide, and it is much stronger so you can use a lot less of it.
The operation of these chemicals is different. Hydrogen peroxide oxidizes by releasing oxygen. Sodium chlorite oxidizes through electron exchange. No oxygen is released when using sodium chlorite unless you add UV light or heat.
Sodium chlorite activated with water utilizes higher concentrations, but it is very effective as a mouth wash, and can be used as a time released chlorine dioxide solution that is very effective against mold and mildew.
When you add an acid to sodium chlorite you form chlorous acid. This is an excellent disinfectant and sanitizer. Using a 60 PPM free chlorine dioxide chlorous acid solution, you can spray down surfaces and they will be disinfected in a minute or two. Chlorous acid is also very good for washing food to remove any pathogens that may be left on it.
When you fully activate sodium chlorite and then collect the chlorine dioxide in another container of water, you end up with chlorine dioxide in water. The advantage of this is that chlorine dioxide does not change the PH of the solution, and you can sanitize areas that may be PH sensitive. Also, there are a lot of uses for chlorine dioxide as a gas, but there are health issues that call for extreme handling care when using chlorine dioxide gas.
We still have some hydrogen peroxide around the house, but have virtually eliminated using it and are using various sodium chlorite solutions instead.