Roleplay is taking on the role of another. I would expect most pirates, assassins, revengers, hell almost anyone engaged in any kind of violence against anyone else, without the protection of a nation-state or similar entity to back them up, who wanted to maximize their chances of success and avoid being punished, to keep their damn mouth shut.
One of the many reasons why I've never even considered playing a piracy focused CMDR is that all of our characters wear permanent name tags. Were I actually role-playing a pirate, I'd be trying to get away with the goods without anyone knowing who my character was. I'm not at all inclined to play a fool who undoes himself in the exposition, a fop who prattles on while his livelyhood makes their escape, or even someone who equivocates on the nature of their business and motivations enough to even consider leaving witnesses alive.
The overwhelming majority of the time I see people mention role-play in these scenarios it's from people wanting everyone else to role play a complete moron for their own personal advantage, rather than see others behave in any contextually plausible manner.
From the perspective of the target there's no discernible difference. Anything that the attacker communicates can be assumed to be misleading or inaccurate.
The target's perspective shouldn't matter, at least as far as how the game, or those enforcing it's rules, are concerned.
My CMDR always assumes the worst, and acts accordingly. An interdiction is an attack and the goals of an attacker are to do as much harm as possible. Without prior knowledge to the contrary, nothing they could possibly say would alter the fight or flight response that was initiated the moment I noticed them.
As a player
I assume the best though...that these are other players of a game we mutually enjoy who are having their CMDRs act in a manner they feel is entertaining and that they are going to follow the letter and spirit of the rules. Honestly, I am rarely disappointed by 'gankers' or pirates in this regard and very few encounters cause me to suspect that someone is attacking me, the player....unless their communications imply otherwise. The ones that remain silent would have to do something overtly against the rules for me to think them a 'griefer'.