If you spend enough time watching nature videos like I do, you will notice that the vast majority of animals are eaten alive by their predators. It's slow, and exceedingly painful and it is ubiquitous. So even if plants were conscious, I honestly don't care. A bear would eat me alive in the most painful way possible and they wouldn't even think a second about it. Neither will I.
I don't care either, I draw the line between human and non-human. Anything you do on non-human is fair game to me. The only reason I may care about animal suffering is because the other human can get angry can cause me trouble.
It might be wise to moderate that position by also objecting to people taking pleasure in seeing/causing the suffering of animals. You may not care about the experience of those animals, but you should still care what effect it has on the human who indulges that side of themselves.
Similarly you should also care that humans are not excessively exposed to scenes of "necessary" animal suffering, whether that be abattoir workers or veterinarians. Having psychological counselling mandated and freely available for these professions would be an ethical improvement for the world even if it didn't reduce the amount of animal suffering at all.