plants for sure do take in and process information, and perform some computations, but yeah i think the key thing is whether or not their way of processing information results in an experience of being alive, and i don't think it does. while i think the set of possible experiences is much more diverse than the subset that looks like our own and has familiar elements like "a sense of self" or "a sense of the present moment" i still find it unlikely that plants experience much of anything. i just don't think they have enough interconnectivity. maybe a mycorrhizal network joining a bunch of plants would get there.