The "less death is better" part refers to the blog primarily with the trolley problem. It's a naive and utilitarian way to quantify those problems and disregards a lot of the why behind the taken decision. My point is that those alternative decisions can still be expressed with logic because they just has different premises.

"Is killing animals for food ok?" has plenty of different premises for both sides, and both sides can be expressed in a logically sound way.

E.g. it's not ok to kill sentient beings, animals are sentient, eating animals kills them etc. end up with a hard no. Those premises aren't universally agreed upon, so even using the tools logic provides us won't give us a clear universal answer on if killing animals for food is ok.

Most of those deductions also come from premises like "less deaths is better". Where people have disagreements when it comes to moral questions isn't usually the deduction itself or flawed logic, but the premise.