It depends.. if the A.I. is simply a repository of the memories of the person, then destroying them would be like burning all of a person's diaries and books they had written... a tragedy perhaps, but not a murder (as killing the person would be, even if they had forgotten everything and were a blank slate somehow).
Now if the Robot is self aware (a true Artificial Intelligence), regardless of what memories it might have or whether it is made of biological parts or artificial mechanical parts, then killing it would be like killing a human being (Morally speaking), the question then is, is it ever permissible to destroy such a being? There you get into discussions of self defense (including in war or law-enforcement actions) where the destruction of a sentient being may be again, tragic, unfortunate, but permissible under some greater good (protecting other innocent lives jeopardized by this being's exercised freedom to commit violence). Do the robots feel pain? Then that would be a side issue (similar to questions of whether one should take extra measures to avoid unnecessary suffering when putting down a rabid dog for example).
But just avoiding the gory bits to scare the kids (and avoid discussions of the morality of killing in any circumstance in favor of just playing an exciting game)? Yeah, trash the inhuman-looking robots, no problem.

I was just thinking the other day of some show that was full of action but nobody actually was killed, it wasn't the A-Team I was thinking of. Much like other forms of more "mature" content, sometimes it can be overdone. If killing is rare in your story/game, then it can be more impactful when it does happen.
I guess in Space Crusade the basic premise is that Imperial ships are traveling in and out of warp space all the time, but sometimes they disappear... and return all messed up and full of armed alien warriors. So it's presumed that these baddies commandeered the ships, probably after killing the crew, and now pose a threat to the Imperium of Man. So if you wanted to cast the Empire as the bad guys you could say they're xenophobic ethnic cleansers who are invading territory and slaughtering them for no good reason. But that's not in the story. The story is that these guys are basically space pirates and unless you give them the option to surrender, that's that. In the backstory the realm of Chaos is where the Chaos gods (right?) reside, and they are bent on the torture and enslavement of mankind (but not utterly wiping them out, otherwise they'd lose all their power too, right? unless they're utterly insane of course). The question for the storytellers (and players) is how they can hold onto their moral high ground in a war against such savagery... if you try to take it past the basic level of a skirmish board game.
Apologies for the omission of this clip Warning: Treknificient ! Even the NA version of Space Crusade is a much lighter, brighter take on the mythos upon which it is loosely based, obviously. I was looking and the series really became "grimdark" and pessimistic/fatalistic in 2nd edition which came out three years after this. But I suppose there were other installments before that which were heading in that direction. Not being a Warhammer expert (merely a veteran HeroQuest fan), I am learning as I go. I need just enough info to understand these board games and the rest, as far as I'm concerned is homebrewed lore as needed to make new adventures... but it is interesting! I'm going to use some of it in my own cross-over adventure sometime.
I can see the "less than lethal" versions coming in if we're playing with some younger more sensitive players, but more I was thinking in a few custom missions where you are trying to avoid bloodshed but still need to take out the bad guys (hostage rescue, quelling a prison riot, other peacekeeping type missions, taking enemy prisoners). "There's one, set for stun..."

Having robots would be more a flavor thing... we already have a mix of biological and mechanical enemies, but some might fit better with a certain theme. Maybe the robotized versions would have modified abilities or stats compared to the other aliens. Hey there's an idea... like the cybermen in Doctor Who or the robo-ninjas in Mortal Kombat, maybe a plot where they are "converting" people into robots. Tragic, interesting...
And yet, any uniqueness in this German version I think is worthwhile to preserve, whether people use it or not.