

I’m not sure I’m replying correctly to your question, but the Roman letters can be traced back to Egyptian hieroglyphs and those were based on physical forms.
My favourite is the ox head - alp - which was representation for the letter A. If you look at A, you will notice, that if you flip it on its head, it looks like a simplified ox head. That it directly traced back to “alp”. I don’t remember the origin of each letter, I have followed a guy called Useful Charts for yeeeeears and he made a video on the evolution of the alphabet and also made a poster that you could/can(?) buy. Which is so cool, honestly.
Not all letters can be traced all the way back to Egyptian hieroglyphs, but a surprising amount can and they all represent objects that the common man recognized at the time and it helped with comprehension.
In case you’re interested in the evolution of the Roman alphabet, you can check out this video by Useful Charts, or if you’re more interested in just seeing it, you can just look at the poster he made here:


















He’s a talkshow host. Talkshow hosts are sub human at best.