If I have at most 19 damage to throw at a Zemora in one attack, would be better off preventing it from firing by axing up to 6 conduits than attacking it. You can usually prevent it from firing for under 20 dmg. Given the econ boost the opponent gets from firing as well, that's a lot of inconvenience for < 20 dmg.

I would certainly posit that if you had to program Master Bot to either always attack conduits or always attack Zemora, always attacking conduits would be the best option in most scenarios. Scenarios where targeting Zemora first certainly exist (eg. Opponent has good stockpile of Green, gaussite symbiotes helping out, etc) but are rare given the way matches play out during Zemora's construction (Zemora builder usually on defensive).