Which is my leading criticism of the idea.
If I'm like "hey that being is clearly reacting to stimuli that could hamper its self preservation and it is aiming to avoid that" and it takes another decade for Neil Degrasse Tyson or somebody you respect to tell that person the same thing about, say... plants, then what's the point of listening to that person ever?
Like, we were allll eating plants - in this example - with the same observation that the anti-suffering person willingly ignored and lorded over us, and now they move their own goal post while acting like we're only eating plants because we're oblivious to their reactions to harmful stimuli. again, example. replace plants with octopus if you need to.
but its an ideological line that doesn't seem based in anything except an arbitrary line. I can go along with desiring sustainable practices. no factory farming but preservation and keeping populations stable. but "omg it can think and feel!?" just isn't something I can be surprised about to draw a line at that. amoebas avoid negative stimuli. there's no need to gain consensus species by species.
My only issue with this is the more we learn about both animals and plants, the more complex they both appear to be. Reductio ad absurdum - we can't eat anything because everything is smarter than we thought. The only truly safe answer is to bio-engineer humans to use photosynthesis.