Stupidity: Luca's parents try to find him by splashing him with water. If they succeeded, Luca's cover would have been blown.
Stupidity: Gunner [Director and Co-Writer Brock Harris] was given a puppy ("Barnaby") by the nurse (?) who told him he was sorry his "[VA] benefits didn't go through." Gunner could have merely refused to take the puppy but, instead, drove away with it - and later threw it out his truck's window while he was driving. (00:24:42 - 00:25:55)
Stupidity: Chad's friend Albert sneaks along the side of the house when Jed Blake and his gang are on the porch. Instead of staying hidden, Albert runs out in the open and is shot dead. Earlier, Chad and Albert also stayed on the porch along the railing when Grandpa started shooting and the gang returned fire. (00:09:10 - 00:10:20)
Stupidity: Possessed child Nicholas made the cross from a necklace pierce Fr Louis in the neck, causing blood to gush out. Fr Peter yelled, "Fr Louis, Fr Louis" as Fr Louis tried to pull out the cross. No one else present rushed over to try to help stop the bleeding or assist him. Fr Louis' sash could have been used around his neck to apply direct pressure to the wound. (Although it might have been obvious that it was a fatal wound to the neck, someone should have at least tried to help). (00:07:15)
Stupidity: Billy gave Skylar (a stranger at the diner who did a "dine and dash", not paying $12 for her food) a ride. She came across as suspicious, angry and "street smart." Billy nevertheless put his envelope containing $500 cash between the driver's and front passenger's seat where Skylar could see - and take - it. When they arrived at the Kite Skating site, Billy got out of his Jeep without even thinking about the money. (Skylar gave the money back, but it could have been kept). (00:19:19 - 00:20:35)
Stupidity: Patrizia Reggiani is no rocket scientist in this movie, but it's quite bizarre that calling the fortune-teller she sees on TV, with her name written in giant letters in two different spots on screen, she asks her "What's your name?" It makes sense for the international audience who may not recognize the word "Pina" as a name, but an Italian wouldn't have any doubt. (00:41:05)
Stupidity: For someone trained like "H", it was absurd that he would run down the center of the road toward masked gunmen and get shot multiple times. It was also ridiculous for him to have taken his son to a location that was potentially dangerous and put him in harm's way in the first place. (01:13:20)
Suggested correction: I'm not sure how much H was trained. If I recall correctly he's a skilled criminal, and all his "training" was faked so he could get the job with the company. Regardless... training or not, all that goes out the window when your child is being attacked. Paternal instinct took over and he was rushing in to protect his son. As for your 2nd point, it's made clear that his task was to simply stake out what was supposed to be a routine truck route. They had no idea the truck was going to be robbed.
Stupidity: The location of the small hole near the bottom of the wood-trimmed wall where Everette passed Sharyn a note and pencil would have taken much more time and effort to accomplish compared to merely penetrating the wall a little higher (where there would not have been wood trimming/baseboard on both sides). (00:10:00)
Stupidity: The Analyst wishes to hide the true identity of Neo from anyone inside the Matrix, so his appearance is altered. But in this new Matrix Neo is also named Thomas Anderson, his name from before he was pulled from the Matrix originally, and he is a famous game developer that created a video game series called "The Matrix." It is frankly astounding that anyone actively looking for Thomas Anderson would not immediately see through this ruse and instead would be fooled by balding hair.
Stupidity: For claiming to know how to deal with Music Ebo doesn't do a good job. He wrestles her to the ground to calm her down which is very dangerous for both the patient and the caregiver. It's only recommended as a very last resort and in both scenes with this neither one required it to be used.
Stupidity: Two oil rig workers were looking at two young ladies in bikinis who were sunning themselves on a boat/yacht. One oil rig worker said, "That's where we should be right now. With them, enjoying the sun, instead of baking in it." Both men had double layers on - a jacket or sweater over a jersey or T-shirt - and one man was wearing a tossel cap. Even if it gets cold on the rigs at night, they did not need to be dressed in warm attire during the sunny daylight hours. (00:10:35)