5'5" is a respectable height for women.
5'7" is very short for a man.
You are still not seeing the point - your repeated questioning of whether he could reach high enough was probably hurtful. He was 'adamant' that he could reach the roof. I think you should have backed off at that point and let him figure out for himself whether he could or could not. He is a contractor and you are a software engineer. Don't horn in on his turf.
And while you didn't mention intelligence per se, you clearly do value curiosity and thirst for knowledge higher than posting memes.
You may not have examined your thoughts on this topic too closely, but you made some remarks that make you come across as feeling superior to him:
That opinion came from very different reasons when we were getting to know each other. I am inquisitive and curious. I like to read, learn and cultivate my mind. He admitted he had not read a book in his life and spends most of his spare time posting memes on Instagram. During lockdown I finally found the time to learn things I wanted and as a result earned two certificates. He just "got bored" (8 months without working - I would do so many things!! but getting bored is not one of them)
I see a good deal of comparing and contrasting here, and not much living and letting live. You don't have to date this man or even pursue a friendship with him, but a comparison in which it is implied that one person has made better use of her time than the other, that one person's priorities and interests are superior to the other's may cause you difficulties. People are different. Even people who never read can be interesting and funny and nice to be around. If they're not your cup of tea then avoid them, but don't be dismissive of them.
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1 I sent him a link with information about it, and I told him that I didn't want to discourage him and that it is great that he wants to learn, but that nobody goes to university for years if we could learn this on the internet in a couple of hours.
2 But was my comment hurtful though? I would not be offended if I asked him how to do an addition to my house and he told me "wait, do you know about permits, structures, codes, etc? There is a reason why I studied for years, it is not like building Ikea furniture"
Some thoughts:
'It is great that he wants to learn' is a patronising thing to say and if that is a reflection of your feelings here, then it's a patronising attitude.
There is a subtle difference between those two statements. The first comes across as a curt put-down, and patronising. The second is more matter of fact and neutral.
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He has some time on his hands and wants to get a project he has in his head accomplished by summer. You think this shows he is living in cuckoo land. But he is making use of his time to better himself, just as you did but in his own way. Can he not get some credit for his initiative here? It seems to me he can't win for losing. He has the right to be wrong about his timetable. It doesn't matter to you at all if he turns out to be wrong. You don't have to save him from making the mistake you think he is making.
You gave him a link to some material that he might find helpful for his project, along with a disparaging comment related to his ability to understand and benefit from it. There are teenagers making money as app developers. He is an architect and has spent many years in university earning his qualification, so presumably he can have at least a good stab at making use of your link. While his progress to date has been slow, he does have something to show for his efforts, and he may be busy doing his contracting work too. You seem determined to see the glass half empty, to disparage, and you are shifting the goalposts here too. His project isn't the sort of thing you would choose but that's ok - we are all different.