Envisioning a world immune to global catastrophic biological risks

The COVID-19 pandemic has highlighted the continuing vulnerability of our civilization to serious harm from novel diseases, but it has also highlighted that our civilization's wealth and technology offer unprecedented ability to contain pandemics.  Logical extrapolation of DNA/RNA sequencing technology, physical barriers and sterilization, and robotics point the way to a world in which any new natural pandemic or use of biological weapons can be immediately contained, at increasingly affordable prices.  These measures are agnostic as to the nature of pathogens, low in dual use issues, and can be fully established in advance, and so would seem to mark an end to any risk period for global catastrophic biological risks (GCBRs).  An attainable defense-dominant 'win condition' for GCBRs means that we should think about GCBRs more in terms of a possible 'time of perils' and not an indefinite risk that sets a short life expectancy for our civilization.

What do historical statistics teach us about the accidental release of pandemic bioweapons?

Historically research on dangerous pathogens, for biodefense and bioweapons, has resulted in disturbingly frequent accidental infections of workers and sometimes escaping to the outside world.  Straightforward extrapolation of those accident rates suggests that large scale illegal programs working with bioweapons capable of posing global catastrophic biological risks (GCBRs) would be released into the world within a few decades.  However, if accidental release rates were so high, then why haven't there historically been more pandemics stemming from such releases?  Examining the known biological weapons programs, especially the Soviet program (by far the largest), we see that they were overwhelmingly working with diseases that were not capable of pandemic spread, with the few exceptions (particularly smallpox) subject to vaccination or having low fatality rates.  This should be expected: clearly the human population could not sustain many high fatality pandemic pathogens naturally circulating.  However, it appears that the Soviet program was engaged in active research to produce deadly pandemic pathogens, although it failed to do so with 1980s biotechnology.  If a future illegal bioweapons program were follow the Soviet example but succeed with more advanced biotechnology, historical rates of accidental release could pose a more likely threat than intentional use of the pandemic agents in warfare.