I built one to try out the concept. It produced something with a faint bleach smell. I then took it apart again because I had no idea what concentration I'd produced, so it was useless - and if you can get testing materials, you can still get bleach, so why bother.

It's like any other home chemistry project - unless you use pre-mixed, pre-measured reagents, you have no idea what the output is, how well it disinfects, how toxic it is, etc. Hypochlorous acid isn't wildly toxic at low doses. Did you make a low dose? What other byproducts are in there? If you don't use it right away, how long does it stay effective? You don't know.

I can think of rare edge cases where I'd try it anyway, but out here in the real world if things are so crashed that you can't buy a bottle of bleach, you're going to have so many other problems that not being able to disinfect your socks isn't going to make the chart.

And in case anyone is considering it, please don't use homemade disinfectants on wounds, for inhalation or for ingestion. You can do more harm than good in the first case and the other two cases are just insane, even though people have suggested them.