It is not the same. It has zero stakes and zero social or psychological pressure.
It is very easy in a roleplayed situation to resist all attempts at persuasion, to agree to a wild course of action, to escalate your efforts until the other side capitulates, to refuse to budge one iota against determined opposition. It is very different to do these things in real life when you don't know the real consequences of those actions, including how other people will perceive you either in the moment or later.
It feels more like 'you're really doing it' because you're using the same essential tool (conversation) but that perception is an illusion because the inputs and outputs are all wrong.