The only reason our brains exist at all is to control our bodies. There are no conscious entities we know of that are just brains in vats.
Why would a being that has no need to maintain biological homeostasis experience something like hunger, tiredness or fear?
That’s what I mean when I say I’ve no reason to believe a thinking machine that has none of my motivations and limitations would ever have a “subjective experience” like my own.
That is, of course, unless we succeed in reverse-engineering human consciousness and somehow deliberately program the machine to experience it.