They're reasonable questions. "Fight" and "self-defense" mean different things
Are they? If someone came to you with two black eyes and said they'd had their wallet stolen by two men would you ask "Yes but were you in a fight?" Would that be a reasonable question?
The point is quite simple: We all know what a fight is until we try and fit Aikido into a fighting, dare I say martial, context. Then mysteriously many Aikidoka suddenly have no clue. They would have us believe that they wouldn't recognise a fight if they were in one. If they see violence on TV they think "I wonder what that is, what's going on? Why is that man waving his arms and legs at that other man?" and when their friend says "that's a fight" they say "Are you sure?". Somehow if a prisioner punches a prision guard that's different to one MMA fighter punching another or a guy punching his wife.
A guy could be punching them in the face and they'd be thinking "Is this fight or is it self-defence?" if the discussions in Aikiweb are anything to go by.
So I don't think these are resonable questions; they're questions to blend with and redirect the discussion away from the question while appearing to be trying to answer the question. Reasonable questions have reasonable answers; none of these questions have answers reasonable or otherwise.
Really it's a technical question; it doesn't require deep thought. What can you do against someone trying to punch you? What can you do against someone trying to kick you? What can you do if someone grabs you and tries to wrestle you to the ground? Are you significantly more likely to avoid harm in these three situations than an untrained person?
If you've answered those four questions then you've covered the bulk of of what people want to know when they ask how good Aikido is for fighting/self-defence. If you go beyond the technical then you're missing seeing the wood for the trees. After all what do you mean by a tree? There are oaks and beech and ash, are they trees or are they wood? That's the level of discussion about what a fight is on aikiweb.