I’m guessing that the OP’s response would be something like this:
What’s better than a broad-spectrum treatment plus a narrow-spectrum treatment? Two narrow treatments, because the second narrow treatment is more widely applicable.
If developing a broad treatment costs less than developing N treatments that are 1/N as broad, which seems to be a main point of the post, then multiple broad treatments still seems like the better approach.
I’m guessing that the OP’s response would be something like this:
If developing a broad treatment costs less than developing N treatments that are 1/N as broad, which seems to be a main point of the post, then multiple broad treatments still seems like the better approach.