For operations, sterilizations are carried out with a mixture of means like chemical disinfectants, subjecting instruments to extreme heat (Autoclaving), etc. but they don't rely on antibiotics. Instruments can be put into environments toxic to both human and bacterial cells. The big difference of antibiotics is that they are toxic to bacteria but not to human cells so they can be put directly into the system. Some bacteria are also developing resistance against chemical disinfectants but here we have a much larger choice.

It's defense in depth.

Yes, sterile technique is used to minimize the occurrence of surgical site infections. Sterile technique, when performed 100% correctly, isn't perfect and prophylactic antibiotics are standard to help mitigate any remaining risk.

Oh, TIL. Thanks for the info! It won't throw us back to the pre-semmelweis era though only to the pre-fleming area.

The field uses "Swiss cheese" as a term for a reason - you can have holes in each layer (and will), but if you have enough layers you'll be okay.

agree. and my next fear is that all of the medical establishment, suppliers, and practitioners who depend upon surgical procedures for their profitability downplay the additional risks and continue to encourage all of us to undergo surgery

Surgeons are already the bane of many infection control specialists.