I at least explained what the problem was with the argument. "I don't think so" is not any kind of improvement there.

Secondly, these animals aren't abandoning their niches, they're losing them due to human activities. There is no room for another species to adapt to it, because there is nothing there to adapt to anymore.

>We try to understand countless things without have a use case in mind at the time of study.

You're making a pretty clear reference to mathematics & science here, but in those disciplines we study things with well-defined structures. We don't study flighty nonsense because it's not ever going to be useful. You shouldn't invoke this phrase to excuse a lack of precision and clarity.

My government has never forced me to do anything with a threat of violence -- I have been threatened with different manners of obvious inconvenience, but if that is no more acceptable to you than an actual threat of violence, then I'm afraid that is an unproductive, reductive, and uncompromising opinion.

Anyway, the argument here is as much about the government controlling the people as it is about the people controlling the government. If the US government turned against its own people militarily, the only way you could recover is if you could regain control of the military and turn it back against the government or if you could somehow get a more powerful military to overthrow it. A revolution from within can only succeed if it controls the actual military.

Really, it doesn't matter if an animal that doesn't exist would 'prefer' to exist in suffering, because that's a purely counter-factual fantasy to begin with. All that matters is whether we should prefer such an animal to exist. Anyone who prefers they wouldn't based on vague moral arguments has to reconcile that with the fact that killing those animals for food is right in line with correcting the 'error' of their birth.

A better way to make the argument is to appeal to things we do actually care about in an ethically consistent manner: how inefficient and wasteful it is to raise animals for food. If you have something that is more efficient, tastes better, and is healthier, then it becomes harder to justify that waste, regardless of anyone's moral position on suffering. Anything else is just an reasonless appeal to emotion.