Hyperbole, any mirror organisms we cook up will be simple and inefficient since they won't be able to make easy use of the abundance of material that is the wrong chirality for their biochemistry. If they escaped they'd starve to death because all the normal life would be scavenging all the food sources much more effectively.

Im really starting to wonder which great filter is going to wipe us all out at this rate. Leaning towards a when, not an if.