Yes, I understand that. And again, I’m not saying that writing left to right is easier when being right handed only because of the ink issue, but because it is easier to see what you just wrote, regardless of the tool you use. Whether I use my right hand to hold the hammer for the left-handed chisel, or the straw to write in the wax, or the knife to carve in the bark.
I’m only asking what made Arabic and Hebrew a right to left direction, whereas the rest of the Western world left to right, if they evolved from the same ur-alphabet. If there is no anwer to this other than ‘just because’ I’ll have to be content with that, but I hoped for more.
One theory that I have heard is that the right-to-left tradition started because it was easier for right-handed people to carve into rock. Imagine holding a chisel in your left hand and a hammer in your right, and trying to chisel out a sentence in the Roman alphabet (your choice of language - English, Latin, Hungarian, whatever…). Since you would be hammering toward the left, any letters already carved to your left would be in danger of being damaged by a slip of the chisel or hammer. By carving from right to left, you ensure that the most likely kind of accidental damage would be done to the left, where there aren’t any letters yet.
Presumably, then, alphabets that were written right to left (e.g. Hebrew, Phoenician, Aramaic) become fossilized at a time when carving into rock was considered the primary means of writing or among peoples that considered rock to be the ultimate writing medium. Alphabets written left to right may have been fossilized (i.e. became “just the way it is done, deal with it”) among peoples that considered writing with a pen on paper, papyrus, parchment, or some other similar medium to be the standard way of writing.
I write both English (left to right) and Urdu (right to left). At least with modern pens there is no functional difference in how you write and grip the pen. I have used ballpoints, felttips, markers, and fountain pens. No problem.
Regarding hammer and chisel, I think you’re missing the whole “chisel” part. When the chisel is gripped with the left hand (for a right hand dominant person), It’s doing exactly the opposite of what you’re arguing (its obscuring the letters you just wrote, when written left-to-right). The hammer (gripped in the right hand) is much further away from the written surface, thus it doesn’t really matter much from a text visibility standpoint. Try it and see.