It used to be that there were four active inventory buttons. The result? Unplayable for most people who tried it. So it was shifted to something with one active item and you could cycle through items quickly based on other buttons. The result? Incredibly annoying and fiddly. The new system was implemented last September or so, and it's worked out the best by far.
Bear in mind with something like valley 1, there were 10 slots but you changed what was in which slot pretty rarely. Here items are coming and going pretty rapidly, making that not really the most feasible. One key thing that was found in older versions of this game was that if the game didn't pause during inventory management, players would get killed unless there was a safe zone to retreat to.
Or if you go waaay back to 2008, this controlled more like Lode Runner The Legend Returns, where you had two slots period (or one at one point), and you had to use your items before picking up new ones. That was simple, but annoying, and made for lots of backtracking. At one point items didn't even stack!
And there were other iterations, too.
All in all, I'm extremely happy with how this is working out at the moment, and goodness knows we've been through tons of iterations. I don't expect everyone to love it, but Zelda does do I this way for a reason. This isn't something I'm particularly keen to revisit, nor do I think it really needs it. I suppose if we wanted to try the current system but with 3 or 4 active item slots rather than 2, that wouldn't be the worst thing. Those who don't want to use the extra buttons can just skip them. But that's more the level of change I'd be open to; a refinement rather than a whole sale course correction.
