I have never felt the need to repair or forge weapons in BotW, ever. It kind of defeats the purpose of the system. If you know where weapons are, you can just restock with every blood moon, and you can still be successful just by grabbing whatever enemies drop when you defeat them; assuming you actually need to, considering it's pretty easy to fight without breaking your stuff constantly. Now, if they wanted to expand the smithies in towns and allow you to make weapons besides just the Champion's stuff, that'd be cool. But I honestly don't see the necessity of it at all when you can just easily go find anything you'd want to make, for free. It's like... what's the point? Why would I spend resources on that if I can just go pick one up for free?
Now, if they were able to change the attributes of your weapon (like durability up and stuff), that I'd call useful. But making stuff from scratch just seems redundant.