Yeah less deeply was only one example, and only the most obvious one. And because many human emotions function in some sense as a commitment device (e.g. if you make me angry enough I will lose control and then you don't know what will happen) they might also ultimately need to learn their way into those dynamics as well, to realize the full value of emotions.

Regarding brains in vats: Yes, I think there would be a tendency to continue without the biological response, and I think this is much of what buddhist dukkha is talking about (being hit by the arrow twice.) That is, there is the experiential or hormonal input, and then there is our learned response to that input, and it is the latter that most colors our subjective experience.

An extreme example to illustrate the point would be a learned traumatic response causing full on panic in response to being startled.

(Though this is all a gross simplification because there is a feedback loop between thought/subjective experience and the hormonal subsystems that sustain or trigger emotional responses, etc.)