The article seems to mostly equate emotional states with consciousness but doesn’t make the case for that equivalence. Paramecia also exhibit negative stimuli avoidance behavior but I don’t think that can plausibly be cited as evidence that they experience pain. I am generally persuaded by Antonino Damasio’s arguments that consciousness is roughly a system “on top of” emotion, the latter essentially being a shorthand for a variety of behaviors related to the body’s efforts to maintain homeostasis. (I’m simplifying and probably getting details of his argument wrong, it’s been more than a decade since I read his stuff.) I am sympathetic to the idea that “lower” animals may have something like mental states or conscious experience, I just don’t find the arguments in TFA convincing.