Not sure what RPGs you've been playing, but I can't think of many cases where that's true. Certainly not any RPG made since, well, the 90s, really.
Absolutely every diablo-like ever (Dungeon Quest, Sacred, etc). RPGs like Neverwinter Nights, the Elder Scrolls, Icewind Dale, Dragon Age, Kotor, Fable, etc... Most of them are formulaic as hell, and it doesn't matter (let's call it "classic"). Oh noes my mentor Beardaf is dead, oh noes evil is descending on the world, must find the Sword of Jewels of The Ring Of Staffs before Warlockor the Warlock, if I do it with a party let's hope Maidena won't be captured or turned to the dark side because that twist would unexpectedly raise the stakes.
Seriously, mileage may vary (if you played A LOT of them, you tend to lose interest in repeated clichés and the ability to invest yourself in them), and also games aren't homogeneous : pedestrian and creative storytelling can coexist within all the main quests and subquests.
But most importantly, that's not the point. What is, is the difference in
players more than the difference in RPGs. Because you can have an excellent story that gets ignored by a player, or a ridiculous one that gets passionately followed. It depends on the people, their mood, their history, etc. Within a same game, people can be attentive or skippy depending on the quest or depending on the day. People can be thrilled by a new story, or be bored by its "yeah, been there done that", or be thrilled again by a return to a classic formula. People can find slight variations fascinating, others can simply see it as samey as a whole. The story is just a component of the game that players decide to find important or not. They can launch the game to be told a tale, they can launch the game to behead gnolls, they can launch the game to stroll in its cool environment, they can launch a game to scrutinize its lore and geek out infinitely about it. There is no rule, and there is no correct way (and even the most derivative plot is new, or new enough, to some). Games tend to maximize the spectrum of enjoyability.
And hey, we're just talking about RPGs here. In fact it even applies to adventure games (many players just solve the puzzles and skim through the dialogues, which are actually not very often as worthy of attention or laughter as the authors think). But it applies all the more to action games that try to wrap themselves in emotional drama. Some people can care, others don't and just launch them for the pew pew piff paff. Insert coin, read blurb and go.