I also have a hard time with learning concepts too if there are handwavey parts of it. I remember by recreating the higher level concepts from lower level ones at times.
To me, the abstraction is an oversimplification of actual, physical, systemic processes. Show me the processes, and it's obvious what problem the abstraction solves. Show me only the abstraction, and you might as well have taught me a secret language you yourself invented to talk to an imaginary friend.
I don't believe most productive programmers learned the quantum physics required for representing and manipulating 1s and 0s before they learned out to program. Abstractions are useful and efficient.
You're more comfortable with a certain level of abstraction that's different from others. I can't endorse others that try to criticize your way of understanding the world, but I'd also prefer if some people who in this thread subscribe to this "bottom up" approach had a bit more humility.
I think part of it comes from believability, or the inability to make a mental model of what is going on under the hood. If something seems magical, you don't really understand what is going on, it can make it hard to work with because you can't predict it's behavior in a bunch of key scenarios. It basically comes down to what people are comfortable with what their axiom set is. It gets really bad when the axiom set is uneven when your teaching it, and some higher abstractions are treated as axiomatic / hand waved, while other higher abstractions are filled in. This is also probably an issue for the experienced, because they have some filled in abstractions that they bring from experience, so their understanding is uneven and the unevenness of their abstraction understanding bugs them.
Like limits in calculus involved infinity or dividing by unspecified number seems non functional or handwavy in itself. Like how the hell does that actually function in a finite world then? Why can't you actually specify the epsilon to be a concrete number, etc? If you hand wave over it, then using calculus just feels like magic spells and ritual, vs. actual understanding. The more that 'ritual' bugs you, the less your able to accept it and becomes a blocker. This can be an issue if you learned math as a finite thing that matches to reality for the most part.
For me to solve the calculus issue, I had to realize that math is basically an RPG game, and doesn't actually need to match reality with it's finite limits or deal with edge cases like phase changes that might pop up once you reach certain large number thresholds. It's a game and it totally, completely does not have to match actual reality. When I digged into this with my math professors, they told me real continuous math starts in a 3rd year analysis class and sorry about the current handwaving, and no, we wont make an alternative math degree path that starts with zero handwave and builds it up from the bottom.
