The learning behaviour is actually much more nuanced than that. This is one of the main papers on it (the Youtube video I linked earlier puts it in a more digestable format, plus provides some extra context from the main researcher’s talks and other papers).

This paper is referenced in the one I linked.

Even more controversial have been Monica Gagliano’s intriguing behavioral studies on habituation and associative learning, which have captured the public’s imagination in a way not seen since the 1973 publication of The Secret Life of Plants [28,29]. Habituation, considered the most basic form of learning in animals, is a decrease in a behavioral response with repeated stimulation that does not involve either sensory adaptation or motor fatigue [30]. Putative habituation was reported by Gagliano et al. for the rapid leaf folding of the sensitive plant Mimosa pudica in response to a mechanical stimulus [28]. Gently dropping potted mimosa plants from a short height caused rapid leaf folding, and the response declined to zero with repeated dropping. Nevertheless, they were still able to fold their leaves in response to lateral shaking, indicating that the decrease in the response was specific for dropping and was not due to motor fatigue. The authors concluded that the mimosa plants exhibited genuine habituation, consistent with an ability to learn. However, Biegler has cautioned that such a conclusion is premature and that additional controls are required to establish the specificity of the response as well as to definitively rule out the effects of sensory adaptation and motor fatigue

The paper that responded attributed most (but not all) of their data to motor fatigue.^[https://link.springer.com/article/10.1007/s00442-017-4012-3] However I do not have the time to get into the specifics of this case.

And to be clear the complex mammals vs plants is the most extreme case, but we can study the stress indicators of bees, bugs etc. to see that they clearly do not desire to be farmed and can respect this by basic application of consent.

I don’t think it is possible to create a clear and objective definition of intelligence or sentience that excludes all plants (and mushrooms!) without excluding e.g. tardigrades, honeybees, silkworms, mealworms, snails, or indeed lobsters.

survival instinct is a very common line drawn. Basically if the organism has the capacity to learn about danger and flee, or defend in some other way, then it does not want to be killed. If there is no such survival instinct (and the lack of such defenses or mechanisms to flee would suggest that there was no evolutionary need for it to evolve such an instinct) then it is safe to eat. It is not possible to evolve a complex memory system and survival instinct without the possibility to use it. Since by itself such an instinct (with no possibility to act upon it) would offer no survival advantage. And just to be clear I'm talking about defenses that are pro-active not reactive. That require pattern recognition. Not just "the bark heals itself after a cut" or "the plant closes in reaction to being touched".

Certain micronutrients that cannot be gained (or easily gained) from plants would be available in simple animals, which could make them a valuable food source in a world that doesn’t eat chickens, pigs or cows. Simple animals can also be valuable for bioengineering. Conventional non-food uses like silk production are also pretty nice.

Again with the "it is pretty nice and cool to have", this is not an argument to inflict pain upon others.