This has to be one of the worst articles I've read on Medium in some time. It's basically giving the same ridiculous excuse for not being vegan that countless idiots have given over the years - "What about plants' rights, though?" - but dressing it up in some sort of verbose, long-winded, pseudo-philosophical bullcrap.

Yes, it is possible, I suppose (although it's a bit of a stretch) "that seemingly non-sentient entities have a kind of sentience that is so unlike our own that we simply don’t recognize it" but since we have no proof of this and we DO have proof that non-human animals suffer, why would we base our morality and actions on this hypothetical possibility? Arguing against anti-speciesism on these grounds is like arguing against anti-racism on the grounds that a vase or a brick might also have feelings - it's absurd.

As for your argument that "sentientist ethical values can lead to a justification for environmental destruction", this completely misses the point that environmental destruction negatively impacts sentient individuals and communities. A non-speciesist approach, therefore, based on sentientism, is a far better protector of the environment than the current state of affairs.

Furthermore, if it turned out, as you suggest, that plants are sentient after all, then a sentientist system of ethical values would, by definition, protect the environment, not destroy it.

Incidentally, I'm not a fan of Peter Singer and I'm definitely no fan of utilitarianism but at least he can string together a coherent argument.