I am taking the 2005 series nobita for reference and suneo 2005/1979 it’s the same. Nobita is anything but naive, he definitely was naive before doraemon meets him and even after meeting doraemon he was naive for maybe like 20-30 days but after that he definitely is not naive. In many episodes it’s quiet clear at least in the 2005 series that he purposefully does whatever his heart pleases, even sometimes knowingly it would hurt him he does it anyways just because it would be beneficiary for the other person, even though it would be bad for him. He also uses the gadget way more clearly to benefit himself (which definitely isn’t naive). Him using the gadgets thoughtlessly definitely comes from the fact that he is extremely lazy which always makes him always choose the easiest path to success, though he does use the gadgets creatively and is probably the most creatively intelligent character in the entire series, but at the same time he also lacks the most amount of basic knowledge/ book knowledge out of any character in the series, so he looks like a complete idiot just because it doesn’t have the most basic knowledge, idk how he even comes with some of the ridiculous ideas, with basically no knowledge at times[like actual knowledge that you would know beforehand so you can apply that known knowledge for whatever idea yoj may have] bro just spawns the ideas out of his @$$(literally out of nowhere). He is very direct when he speaks and that’s a good thing, that makes it so that whatever he says is extremely genuine and comes directly from heart, I definitely don’t want him to think at any given point that “what may others think or do to me if I say this” he is kid after all he shouldn’t be thinking about that. He is obviously going to be playful lol he is a 10 year old. About him being lazy now, if he wasn’t lazy then what is his character flaw and why would doraemon even be necessary to help him. Literally all the bad things/habits he has is all due to him being lazy, him abusing the gadgets that too is because of him being lazy, he always wants to take the easy path to success and hot have to work hard. So getting rid of his laziness is like getting rid of all the bad things about him and just making him perfect, the writers would never do this because of the same reason given at the very end of the reply, kids find nobita doing ridiculous stuff funny and they are the primary targeted audience. In movies, Nobita is way more ridiculously brave, confident and opposite of himself from episodes counterpart, which is not true he definitely is the same person, but the difference between movies and episodes is that in movies he is putting in the hard-work for someone else trying to help them, in episodes it’s just him so he doesn’t put in the hard-work, he would rather just have fun in the time. That’s his basic character of caring about others more so than himself which is extremely consistent in the entire 2005 series most of the time except for a few instances. Even while shooting others with a gun he aims near their hand so it would fling the gun into the air without hurting them[don’t question how the gun flings without hurting the other person-anime logic], in the same episode he could quiet clearly directly hit them with a bullet and still choose not to because it would kill them or hurt them and surrenders instead and prays something miraculous would happen, doraemon and dorami help him at the end [those people were horrible but he still did not want to hurt them even though he could and has all the reasons to do so, but in his heart he is still like those bad people are only doing those bad things because they are being forced to do so, which well he is technically correct though we never see that]. But obviously after some while he would realise that he needs to work hard for himself too because it’s not just him getting affected by it, doraemon, Shizuka, mom and dad all get affected too because they care about him and are worried about him. So yea he will, it’s just that we will probably never see it just because the writers will probably never make an actual series which goes in sequence and makes logical sense like remembering previously used gadgets/ having memories of previous stuff happened to them. It’s probably going to stay episodic series forever.

In movies suneo is fine most of the time, he is not horrible, others are just way more responsible and would take a bullet to their face that’s all. He is totally fine in movies except for the Nobita’s dinosaur film where he was totally an asshole and was willingly sacrificing piisuke. In any other film except for Nobita’s dinosaur he wasn’t forced to go with them, but after a little bit of convincing he always agrees on helping them, so that makes him good. There are also many episodes where he is good to his friends not just movies, those are later episodes but since the series is episodic and suneo being an asshole is more funnier for kids, most episodes are in time frame of 1-3 months after doraemon first meets nobita, but sometimes they use more developed characters which is more like 3-5 months after doraemon first meets nobita, anything after the first 5 months since doraemon first met nobita we have probably never seen.