Interestingly, the whole upgrading weapons thing was sort of implemented in TOTK, via the whole weapon fusing mechanic, though they still break.
But back to BOTW, it’s meant for you to save more powerful weapons, and not rely on combat as the only manner in which to engage with both the world and the enemies. Plus, some of the more useful items are found through exploration.
Heck, you can even scavenge the materials needed for the Ancient Arrows through finding and interacting with decayed Guardian remains.
Also true, however my contention with the system is that you're removing one of the game's central pillars when you make the combat unrewarding. Even if you are creative and fully utilize the environments, or in Tears' case the Zonai materials, to their fullest what does that actually get you? The loot pool is incredibly limited and typically what you get is limited to crafting materials (monster parts or meat from animals), weapons (which is the Oxcart Paradox in action), rupees (which have a very limited usage due to the ease of farming and lack of shops), or gems (which are only good to use for dyes or as a proxy for rupees, they're also under the "crafting materials" category in Tears).
The only reason to engage with combat at that point is either because you must do it for the purpose of quest progression or for simple love of combat but the combat system being so shallow actively sabotages that incentive. Were there genuine differences in weapons beyond aesthetics, raw numbers, and the very occasional elemental weapon, then this might be worth it to trade a weapon you're kind of lukewarm on for a weapon with a skill attached to it or a moveset that you like. And even
were that the case the weapon durability system then disincentivizes and punishes you for actually using a weapon that you like by ripping it out of your inventory and telling you to eat shit by breaking it (usually within one or two combat encounters) with no option to repair and replacement only possible through scavenging.
Zelda games moving forward should seek to solve this problem by diversifying and expanding loot pools, adding more use cases for rupees, add back in more complex combat in the vein of what they started to implement with Wind Waker and Twilight Princess, add true variety to weapons by giving things like stances and movesets that vary between weapons in the vein of a Souls title, and finally by implementing a system in the vein of Link's Adventure's leveling system which would allow you to allocate points to boost your skills and unlock abilities and powers. If Zelda wishes to be more open world that's totally cool and I would wholeheartedly welcome a Zelda 1 style game with BoTW/ToTK style open world exploration combined with the classic dungeoneering of OoT/MM/WW/TP, doubly so if they combined the two in such a way that genuine exploration of the dungeon is also needed where you would need to bring in outside objects to complete puzzles. But on top of that I think that the addition of leveling mechanics would also be nice in order to build Link the way you like in order to better utilize powers and weapons that you also like more similar to a Souls title or Elden Ring.
Nintendo's big issue is that they always take one step forward and one step back. Breath was great for running around the overworld, fucking around with farming, and the shrines were generally okay. But everything else surrounding those peaks were some very deep valleys. When you're making an open world game you have the three pillars of Exploration, Combat, and Story, and unfortunately for BoTW the Story pillar is only acceptable at best and the Combat pillar isn't solid at all, ToTK is worse because neither the Story nor the Combat pillar stand up even if the Exploration pillar is as strong or perhaps even stronger than BoTW's.
(Edited primarily for spelling)
) Is it that unreasonable for Nintendo to have made it so that they can upgrade your weapons too? 
