I believe you, but this is the first time I've heard your position, so if you've repeated it here, my sincere thanks!
My position isn't as black and white as yours, but I would say that a person can lose their "civilian" label if they are aiding and / or abetting terrorists.
If you say that Gazans have had no choice but to aid Hamas for the last 20 years, then again, their blood is on the UN's hands, because EVERYONE has know for years and years that Hamas was using aid money to build it's war machine.
If Gazans have had a choice in aiding Hamas, then they are no longer civilians, IMO.
What qualifies as "aiding and/or abetting terrorists"?
For instance, if someone donates money to, say, the Russian or Ukrainian army during the current war without participating in combat themselves, do they lose their civilian status?
Many al-Qaeda supporters argued that people who voted for Bush or Blair weren't civilians and were justifiable targets. What do you think of that logic? Again, just to state my position unambiguously: I think that logic is dangerous, and I fully reject it. I draw the line at participation in combat.