Do you need a story for Tetris?
OK I mean if that's the direction you wanna take this discussion fair enough. I'm not at all convinced you're actually asking this in good faith, but in case you are:
Hollow Knight goes out of its way to place this character in the world. People speak to you. People speak to you
about not going into the place you keep going into. It is designed to get you to ask questions about what's motivating your character, and doesn't bother answering them at all at least in the game's first many hours. I'm not through the game so I don't know if they're ever answered. If they are, but later, or more slowly, it is completely valid to criticize the pace of the game's storytelling.
Tetris is abstract and doesn't make any effort to place the player in a world. You're not a character. The blocks are not invading aliens to be cleared. You are not trapped in the bottom of a well.
Games are criticized according to their intent. I've never once considered the
motivation of my Ninja Man in N+. He is an excuse for the mechanical platforming action to take place, and the game makes clear through its design that he doesn't matter. If the game had a GLADOS-like AI taunting him upon death, or if stages had secret areas, I might start questioning who he is and where he is. And the game's handling of that character motivation, storytelling pace and world-building would now be now in bounds.
A good example of this in action is how you saw way way more people questioning the nature of Mario and his adventures once we got to explore New Donk City. The structure of the games (and their explorable spaces) prior to Odyssey never really invited people to give it as much consideration. When Mario is bopping around Dinosaur Island or Outer Space his adventures are an abstraction. But put him in a more mundane, recognizable, realistic setting and his platforming antics can begin to feel a little bit more strange and even somewhat unsettling. Even though the gameplay is the same. New Donk City, by its design, invited players to question Mario's quest and to say "maybe this is a little bit weird..." in a way that was less appropriate before.
Incidentally, puzzle game makers, like Tetris, get to decide for themselves which way they want their game to be presented. With a deeply-entwined, well-executed story (Braid), or a more so-so story (The Witness), or a great story (Portal). Portal could have been a collection of abstract puzzles, and as long as Valve stuck to that, no one would be asking themselves "But who is holding the Portal Gun...?"
(This is not 100% cut-and-dry BTW. Even without GLADOS or the ratman environmental storytelling in Portal, things like the death-lasers, respawning mechanics, elevators, and so-on may still have invited some questions about Portal's nature. But I think my key point here still tracks).
Anyway, back to Hollow Knight. As long as people in this world keep talking about how dangerous and foolhardy this place is, and making oblique hints to me and my nail, it's completely valid to knock the game for a lack of
a single screen of introductory text that explains that You Are a Hollow Knight, and that that means X in this world. You've come to this land to seek your fortune / uncover your history / because it is here - and then the game opens.