I think we need to kill the fantasy of having testing environments for most software. For stuff like Airplane control, pacemakers etc. it’s absolutely worth it.

I think we need to kill the fantasy of having testing environments for most software. For stuff like Airplane control, pacemakers etc. it’s absolutely worth it. For most organizations serving APIs with an acceptable nonzero failure rate, using canary deployments and other techniques provide almost all the value you would need.