Ben did recognize the droid but he was being secretive like he was through out the new hope. He was telling truths from a certain point of view to manipulate Luke.
Ben not knowing that there is another? He probably did know about leia, but the leia he knew wasn't able to use the force to breath in space, survive explosions and fly back to safety. She never exhibited any force powers in front of Ben, he knew there was another skywalker but he truly thought luke was the last hope, he didn't consider leia a jedi or force sensitive.
R2 didn't know about luke because like 3po his mind was wiped at the conclusion of episode 3.
Death Star took some time to charge up and fire, we also do not no how long it would take to recharge after firing, Maybe they didn't blow up that planet because they couldn't do it and shoot the rebel base again fast enough. It would have alerted the rebels and they would have left.
See these are weak answers to these questions, just as weak as the ones explaining things in TLJ, or Raider or any other film.... plus many of these explanations have taken literally decades to surface.
I can blow each point away, but it’s a waste of time because you LOVE the film....and will vigorously defend it, because of that love no matter how big a plot hole.....
Example: you expect someone to believe Obi , made a huge deal to hid Luke and Leia but didn’t think about Leia being the “other?” Why would he hid either of them? Unless he believes they could be the key to defeating Vader. So basically your telling me , Obi was only concerned for the male child and figures Leia won’t have the force? A Jedi who serves with female Jedi???
The point is , that because you love the film your willing to accept the answers.
And there is nothing wrong with that, I do it too...
The problem lies (which no one seems to get) is , at this age, those plot holes we so easily see in any film , are part of what makes us not like them anymore...it’s the reason half the people on the forum “say” over and over is the REASON, they hate it.
Tell me you don’t like Luke’s arc? Tell me Kylo is a weak character, tell me the space chase is a bad plot....
But the “holes” exist everywhere in all films....
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