Would the WordPress blog need a sign off each time the style is updated... maybe, css is software, fonts are software. If you adjust a plugin or something, that probably needs a signoff.

Do you need a signoff when you update an excel sheet? Maybe only if it's published.

Do we need specific licensing to assign liability for public harm? Could we just not legislate liability on the operators of software causing public harm, and then people would be less likely to operate software in public unless the operator deems the risk low or the provider of the software offers indemnity (most likely in exchange for $$$$$).

I don't know the exact answers, but this lands near building a shed vs house in your backyard.