> That's like trying to prescribe some sort of attributes to language by looking at ASCII
Which is a fruitful approach [1]. That said, I doubt everything else you wrote, too. I can't make sense of your comment.
> The final point being, that if there actually was such a strong symbolic influence that it managed to survive thousands of years to make it to modern English, you wouldn't expect all these other forms to have also developed using the same rules that led to arm.
I'm not quite sure which "same rules that led to arm" you are talking about, but If you mean sound laws, then it is quite obvious that "such a strong symbolic influence" might lead to a sound law in the first place. Not just "Arm" but a bunch of symbols.
You probably don't speak German so let give you another hint: An archaic German name for the eagle is "Arn" (now "Adler"). Coincidence? The symbolism is quite strong with this one, as the figure of the German parliament and incidentally the Egyptian hieroglyphs are heavy on ornithology, too. And it is notable that other PIE languages derive arm not from latin "bracchium" (from greek ...), hinting at a more complicated case and indeed, perhaps Egyptian influence (why not). However I'm sure you'd find the difference between h₃érō (>arn) and h₂er- (>arm) appreciable. I don't so much, because you would just have to go a few more steps back, perhaps, to find a common root.
There is an insurmountable amount of theories and you dare to arm chair a hazard guess that Egyptain as root would be out of the question base on hypothetical sound laws that are in no small part based on the assumption that Egyptian couldn't have played a role in it. That, my friend, is circular reasoning (and appeal to authority).
bʰer- ("to bear, carry") fits the usage of arms anyway, and I'm sure an eagle carrying away a bunny is an impressive sight, too -- but I'm rambling.
Still, there's more: Bird wings are like arms, aren't they? Ancient Greek pterón* -- there's er in it, that's good enough for me, pashto has wozzar; Persian has bal, Latin ala -- still close enough -- and Somali has baal ... not too distant to Vol as in French "voliere" (aviary), from Latin volo (I fly), from weǵʰ (to bring transport). Zazaki (according to wiktionary), literally has per* (wing) as metaphor for arm.
Sanskrit has pakṣa, Punjabi has paṅkh, Urdu has pankh, too, but Punjabi has also par. Maori has parpau. This is most likely of pre-PIE origin, I think. There's also navajo atʼaʼ; Quechua: raphra, rapra, likra, Kannada: rekke, Malayalam: ചിറക് (ml) (ciṟak). I rest my case. Obviously I am just picking the translations that I deem a fit and obviously there are gaping holes in my argument. I'm writing an internet comment, after all, not a dissertation. So I can reasonably lean a bit out of the window and try to read from cracked pots. I Imagine a pre historic hominid flapping the arms and screeching "ar ar" to describe a bird, an eagle perhaps.
Anyhow *bʰer- would explain bracchium, somewhat, disregarding any sound laws which I didn't bother yet to learn because THAT seems implausible, to derive "laws" from hypothesis and being so fixed on them as if they had been actual law (Which, given nationalism and racism isn't all that far fetched, but still a far cry from a natural law).
Although, wiktionary doesn't have the translations to Egyptian for either of these words and I haven't installed a proper font to read the table from the article, so I'm kind missing the point?
> Greek ἁρμόζω, related to putting together
compile[1] Zhang, Lecun "Byte-Level Recursive Convolutional Auto-Encoder for Text".
https://arxiv.org/abs/1802.01817