So the author itself just makes things way too obviously fake for things like gacha. If they were really being serious I think they should of added the probability of each draw and then randomized it for each time he "cleared" the dungeon, because right now its just "I cleared it on my birthday and wow I got x" and a bunch of other quote on quote random probabilities that just feel really fake.
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Then you have that the main character is a idiot. I'm guessing this is caused due to the author just not thinking about certain outcomes, but it really feels like at times he has absolutely no understanding on the dark side of humanity despite supposedly being an adult in our world.
So, he basically creates revolutionary level up tactics by finding out how to level up skills (Basically like a game) and different skill acquisition requirements where its said if they get out could start the commoners uprising or a war. Despite this he tells the knowledge to his entire family without holding pretty much anything back, including his 11 year old brother through a book. First, 11 year olds aren't the most trustworthy but second the book could also very easily be stolen with this very important information inside.

Now, I'm not really complaining about him telling his family. Personally I would say telling the maid and butler is beyond that, but whatever thats fine. The issue comes when he does things like admit that he is grinding the goblin boss solo, something that nobody has done at his age, or other things like this.
A perfect example of this is when he is selling the water orb. The merchant was his fathers old friend, but that does NOT make them trustworthy. When the merchant asked if he was okay with selling it he just casually admits to having another one, when the thing is worth 3 mil. (I believe it said it was equivalent to yen so that would be appx 30k, which then adds a plothole of these things not actually being that expensive, but I digress) and if these things are so valuable why are you admitting to someone that you have others for no reason.

There are just countless examples of this, where the main character acts in a way that has absolutely no regard for the fact that bad people might want to take advantage of him.
He is just s*upidly naive in a way I wouldn't expect for someone from our world. When the adventure guild master tells him about how nobles monopolize resources for "the people" he just accepts that without a second thought. He writes down that he is an appraiser when becoming an adventurer for no reason, when he could of easily just did swordsman and not given away that he is a rare class.

Another example is telling the king the clear conditions for the basic dungeon, something that was hidden, for literally no reason. While I haven't gotten that far if every person clearing gets the first time clear then countless artifacts can be obtained which can lead to war.

My overall point is that he just acts with absolutely no regard for how his actions can have consequences, and never once thinks its a good idea to possibly hide something like an artifact from his family. While you may trust them there is also no reason to explicitly share everything with them, and in doing so what if they say "the king collects all artifacts" are you then just going to give it up?
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Secondly, he is also s*upid when it comes to thinking just slightly outside the box.

I'm not going to go into all of the examples but a basic one is in the special dungeon... He found out that if he steps in and then leaves it summons and desummons the boss, yet when he first challenges the third boss instead of going in -> appraisal -> instantly leave in order to process the information and come up with a strategy, he instead decides to charge right away despite supposedly learning his lesson.

Some other basic examples is use your spells for some f*cking utility... Utility is so f*cking useful, but instead he treats it as if [I cast water arrow for 5 damage] is the only option... Try using water wall to block your opponent, try using tsunami or flood or whatever its called to drown your opponent, there are so many f*cking possibilities that he just never even thinks of trying.

Another thing is his weird f*cking obsession with not apprising other people since its "an invasion of privacy" which is just f*cking dumb. While you can argue morals and all that sh*t of it, the simple fact is that when appraising someone (like his mom) he can find out information about possible skills like fire magic or staff arts, he could potentially learn titles, ect. so he should be f*cking appraising every single person he meets in order to try to learn as much as he can about different skills.
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Honestly, more here than I expected... The story isn't that bad, but you do need to shut your brain off to read it... I personally have honestly enjoyed it, with the periodic frustration at the main character doing something I think is s*upid or the author having "random drops" that are perfect. Its not great, but its not bad so if your looking for something to read I would say give it a shot.