Can you actually explain why you want it, why it shouldn't be realistic, and why it belongs in D&D rather than Minecraft the tabletop RPG?
Because frankly, I just can't see the appeal.
Did you skip the entire middle of that post where I explained one of my favorite and most beloved characters, and how crafting was central to his identity as a character?
I had another character, he was a jeweler. He was a Storm Sorcerer who started as a petty thief as a child, broke into a jewelers shop to steal a gemstone. Turned out, it was a magical, elemental gem which fused with his body and nearly killed him with the power of storms. He was found, raised to be better, and to worship Waukeen. His goal as a character was to hone his craft and make a necklace worthy of the Goddess.
Why do I want to have characters who make wondrous things? Why do Barbarian players want to slam people through stone walls? Why do cleric players want to call down the wrath of the gods upon the wicked? Why do Wizard players want to unravel the secrets of the multiverse? Because those stories speak to us.
There is an element of ownership, of pride, in being able to state "this is the thing I made, which has shaped this story". In having the skill to create, not just destroy.
Why shouldn't it be realistic? Because DnD doesn't have time or space for that, for one, and for a second, because stories of epic fantasy don't often conform to realism. Also, as much as people rattle the bars about realism, in actuality... it isn't that realisitic. Oh sure, plate armor and chain mail take a long time. But per these rules it will also take you a full 8 hour day to make a knife. Have you watched Forged in Fire? They do it in an hour. They make swords which the rules say should take 2-3 days in an few hours. Brew a keg a beer in DnD? a single day. Actual brewing is a much, much longer process.
So, it isn't realistic ALREADY, therefore why should we accept this form of faux realism that seems intentionally designed to make the process impossible. We want these in the story for story reasons, not to be a reality simulator. And if it ends up taking a smith character two years to equip their party, then everyone is just going to either ignore the rules or they are going to skip over what could be a deeply impactful story because they simply cannot have the space for that sort of endeavor.
And as for why it belongs in DnD? Because DnD is the premier fantasy role-playing game. Why SHOULDN'T we have magical smiths? We literally touch upon these concepts. The dwarves of Norse myth are smiths and crafters, yet my dwarf Forge Domain Cleric is going to have to use magic, not skill, to make anything in any reaonsanable time frame? I can't make an elven-forged blade like they used in Lord of the Rings? I can't emulate DnD stories like the story of Bruenor Battlehammer forging Wulfgar's weapon? Why is it that only Minecraft, an IP barely a decade old, is allowed to emulate something as vital to myth and human culture as making things?