Many people generally don't change boards enough, yes. And keeping plastic boards after they are quite deeply grooved is a problem.
If your dishwasher doesn't have a sanitize cycle (or you aren't using it) you may not be getting hot enough at home anyway to be up to the standard a commercial kitchen would need.
This is wrong (at best outdated). No dishwashing detergent sold at your local grocery has chlorine bleach in it. There are other non-chlorine bleaching agents in some formulations.
You seem to be correct, at least based on review of the MSDS for a popular powdered dishwasher detergent, it's using oxygen bleach (peroxide). Pretty sure it was chlorine bleach in the past.
If your dishwasher doesn't have a sanitize cycle (or you aren't using it) you may not be getting hot enough at home anyway to be up to the standard a commercial kitchen would need.
Of course you may not have a dishwasher at all.