[nradov]

Some level of pre-existing immunity due to prior exposure to other similar coronaviruses is possible but hasn't been confirmed.

https://www.ijidonline.com/article/S1201-9712(21)00571-3/ful...

Many patients who are exposed to SARS-CoV-2 quickly fight off the infection with an innate immune response before the adaptive immune response really engages. That can happen with no pre-existing immunity. Some people just have better immune systems.

[native_samples]

Are you trying to define an immune system that can fight off SARS-CoV-2 without having seen it before is not "pre-existing immunity"? If so isn't that merely playing with words? You seem to be agreeing with what I'm saying but arguing that the terminology should be different.