While certainly interesting research, I don't think this necessarily supports plants having emotions and/or inner lives so much as it demonstrates a sensory-feedback loop. That said, whether we consider that as "pain", or what organisms we consider capable for feeling pain is an interesting question. I frequently bring DFW's Consider the Lobster up in my personal life just because it challenges our definition of "the capacity for pain" as convenient for peace of mind.

FWIW I don't really bother trying to make ethical arguments for vegetarianism/veganism because of these tricky definition problems. I think it's a bit easier to argue for reduced meat consumption for ecological reasons, or to reduce the need for factory farming, etc.

From a dietary perspective it's mostly irrelevant: due to thermodynamic inefficiencies, raising and consuming animal( product)s will inevitably involve farming more plants than eating them directly.

So unless only some plant species have emotions, veganism is nevertheless the best one can do (short of synthesizing food from scratch at a molecular level)

From an evolutionary perspective, I don't see why plants would have emotions. In animals it makes sense as a mechanism to steer our actions in a more survival-prone direction.

But AFAIK plants have extremely limited agency, so I don't see why evolutionary pressures would favor the development of emotions in plants .

A chemical response to vibrations caused by insects chewing doesn't imply pain or any other emotion.

Animals feel pain in part to learn in a dynamic environment, for example to run away from the source of pain. What evolutionary advantage would there be in a plant that feels pain or emotions?