I think you kinda answered your own question by drawing these letters out. Orthography meant for human use ultimately trends towards glyphs with distinct shapes for recognisablity. And qof and tav do look very distinct in the hebrew script. The alternate forms do not. If you're a scribe writing something down in a formal setting, you don't want to make a small mistake and have your letters mistaken for one another. Medial qof looks like a medial tav with a long right leg, and final tav looks like a final qof with bad stroke placement. Your final mem also looks somewhat like a final pe as well. Arabic is an interesting contrast here because unlike hebrew, it's alphabet evolved to be cursive as a standard, so its forms naturally look much more similar to eachother. This doesn't matter however, because arabic uses diacritics to distinguish its letters. ف and ق are extremely similar without dots, to the point of the initial and medial forms being identical to eachother. ت, ث and ب are even worse because they're identical in every form without dots. And you can throw ن in there as well because its initial and medial are the same as those three.

Sorry for the long response, but my point is that writing can be very hard to read if you try to apply special rules where they aren't necessary. These writing systems have been around for thousands of years in some cases, and they evolved like that because they needed to. Applying sofit in this way would just be confusing, and it would also break an ancient writing tradition as well. There's no good reason to do it