The shape of the letter in the שטמ according to Judaism

As is known, there is a debate about which script the Torah was given in, whether in ancient Hebrew script (Daetz) or in Assyrian script (Aramaic). And from research into the development of the script, it appears that the Torah was indeed given in Hebrew script, since this is the script that was here in the region, and the Assyrian script was not found here. It arrived later than the exile. In any case, the aforementioned script at that time had a different font, which developed over the generations to the script used today. In any case, it seems that Ezra wrote in a different font than what we know. Even in the Dead Sea Scrolls, the script differs in many ways from the script that we call Satam script.
Even if we assume that before Ezra there was no problem changing the font, and he fixed the script that was customary at the time in order to preserve the Torah and forbade any change – it certainly did not reach us in the way Ezra wanted. So why is there a citation in the poskim for every tag when it is clear that not everyone writes like Ezra!
And why assume that Ezra corrected not to change the font, if the text of the Bible can be preserved even if there is a change in the font? Why is it required of all the scribes of the Satam to write in a certain way, when there is no parallel to such a requirement anywhere? It is clear that every scribe has a slightly different script, even though in the writing of the Satam there are many things they try to compare the writing of! And the same is true of other writings, where no two writings are identical.
Thank you very much!!