It's not a strange thing to ask. It's a perfectly valid thing to ask. How does a headcrab, with its tiny primitive eyes, could clearly read and understand signs and texts in English? How does a zombie capable of navigating complex environmental hazards? By tapping into the remaining cognitive ability of the host? Kinda wanna tag this as lore now.
7
Half Life Alyx is full of zombies fixated on signs. Especially that one Zoo Worker zombie pointing and staring into children's drawings, trying to grasp onto the last piece of humanity it can find.
In light of this (pun intended), I'm making an edit where all the signs are obfuscated. No more 20/20 vision on headcrab gear. You just got to guess and bumble around like the zombie that you are.