Not terribly often in Zelda games is there an overworld progress blocker tied to dungeons; most have some element of non-linearity, or the progression is tied more firmly to narrative events. It isn't Super Metroid.
Second of all, this doesn't make any sense. You seem to be angry at the ludonarrative dissonance the blockers cause, but you're totally okay with preconstructed dungeons *all* across Hyrule that precisely require four items that can only be obtained in four exact shrines that the player *conveniently* finds outside his chamber of resurrection, and cannot move beyond until they're completed? It's nonsense. We accept these things because we understand how games work, but don't pretend that BotW is some bastion of realism in this regard.
Finally, most of us are complaining about the dungeons' size, complexity, and end bosses, not that there isn't a specific item you obtain that affects further progress in the game world. A Link Between Worlds manages to have fantastic dungeons without progress gating, and these divine beasts fall very, very flat for me.
