Programming languages are nothing like natural languages
But linguists have approached this question from time to time! The main stumbling block is highly literate people are inclined to think of writing as language but it's not, quite. You can have multiple writing systems for the same spoken language, or be fluent but illiterate. But you can't comprehend a writing system for a language you can't speak, barring disability.
So programming languages do have grammar, but not the other components of a language. Idioms in programming are a metaphor referencing linguistic idioms but structurally they aren't the same. Programming languages are more similar to writing systems, and a lot of linguistics findings do apply to them when taken in that context.
You can play around with this idea if you want. Try to convey meaning to someone using only a programming language and nothing else. This is tricky because they embed our other writing systems, so you need to be careful not to accidentally convey meaning with eg variable names. Might be best to use something like brainfuck or piet that prevents that entirely. If it's a language in the "human languages" sense, you'll be able to convey any arbitrary meaning to another person who knows that programming language, even if you don't share a spoken one.
What ends up happening is you can only do this if you reference a shared spoken language. So you can warp a PL into a writing system, but you can't use it alone to communicate.
My question was "would natural hyperpolyglot be better capable of learning/using programming languages", and I don't think any of what you said tells us one way or the other. Yes, the things being expressed with programming languages are different from the things being expressed with natural languages, but they are both designed for expression and communicating meaning. I'd love to see studies on whether there's any relationship between being able to easily pick up and retain human languages, and the same for programming languages.
edit: note, that I'm not even asking if someone with an aptitude for human languages would be good at using programming languages. Obviously the logical components, required for doing a lot of things with them, are a completely separate skill.
I'm only wondering if he'd have an aptitude for learning a language, in terms of syntax, grammar, standard library and associated methods, idioms.
I am not aware of strong evidence for linguistic relatively. Only some light stuff like some two words rhyme in a language so they are more likely paired in music and poetry than in other languages where they don't rhyme.
It is much more plausible that human understanding of the world has shaped language. We can expand our vocabulary for our needs. Skiers of any language likely know more words for snow than speakers of their same language who only want to hang out on the beach.
At least that's what a linguist suggested to me when I lamented my inability to learn some foreign languages as well as peers.
Example: a circuit diagram. You have a transistor and some other components, and if you know the language you can recognise it as an emitter follower. It's a very concrete and clear mapping.
There aren't many things you can do with a transistor. When you've learned them all, that's basically it.
Human languages are much bigger. If you ignore the alphabet level and start with words, there are thousands of symbols (tens of thousands for advanced users). And most of language is about implication and context.
If a partner says "What time will you be back tonight?" that can mean anything from "Because my car is still in the garage, can I borrow your car?" to "Are you still having an affair?" to "Will you make it in time for curfew?"
In most conversations and a lot of writing, the words are hints, not explicit mappings to defined meanings. You can parse an immediate meaning without knowing the context, but not the full meaning.
So it's a much harder problem. You have to learn basic grammar and vocab for tens of thousands of symbols, then learn standard basic exchanges in social situations, then special forms, idioms and social register, then implication and subtext.
I'm afraid I may sound stupid now. Why did you have to add the "barring disability" part?
He might be making different sounds but the meaning is the same, with some culture specific exceptions.
Programming is very little like communicating and it's a lot more like engineering.
The guy might struggle with picking up programming to begin with though, it is indeed a completely different thing from human language.
The skills involved in picking up a natural language are going out and schmoozing with people who speak that language.
This is not actually a skill set that people who are good at picking up programming languages are known for.