I basically agree. The following is speculation/playing with an idea, not something I think is likely true.
Imagine it's the future. It becomes clear that a lab could easily create mirror bacteria if they wanted to, or even deliberately create mirror pathogens. It may even get to the point where countries explicitly threaten to do this.
At that point, it might be a good idea to develop mirror life for the purposes of developing countermeasures.
I'm not that familiar with how modern vaccines and drugs are made. Can a vaccine be made without involving a living cell? What about an antibiotic?
There's The Bayesian Conspiracy's discord server. No need to listen to the podcast or to related podcasts to participate in discussion.
They don't need to solve the whole Halting Problem, for the same reason you don't need to contradict Rice's theorem if you had some proof (which I take as an axiom for the sake of the hypothetical) that the predictor was in fact perfect and that it is utility maximizing. Also, we can just try saying that there is a high probability that they will do this. Furthermore, you can imagine a restricted subset of Turing machines for which the Halting problem is computable. But also the only computers that exist in reality are really finite state machines.
For a treatment besides Tamiflu: https://en.wikipedia.org/wiki/2009_swine_flu_pandemic cites the who and CDC stating that H1N1 developed resistance to Tamiflu but not Relenza
The treatment plan at the time included Tamiflu/Relenza/experimental third thing (FDA approved for flu treatment in adults since 2014)
I think 2009 H1N1 is a good example of how things could go, as it happened in the modern day.