That's what I fear, too, and what I actually expect it to be.
The only glimmer of hope is if they create a good sci-fi story independent of any particularities of Tetris, then use Tetris as a general tool or concept that fits in the story.
Something like this:
BAD
- Making points by filling lines.
- Getting fed random Tetris pieces one by one.
- Having four lines filled at a time being called a "Tetris".
- Basically, anything that makes it look like an episode of Yugi-Oh, where the characters actually play exactly the same game as people do in our real world (unlike in the Pokémon series, where they are not playing a video game battle, but a real battle without "HP" or "TP").
GOOD
- Mysterious blocks used to build something (basis of creation).
- Code inside of them needs specific combinations to mix them.
- Scientist who created/discovered them is Russian.
As long as they do not try to make a story as if they were "in-game", they may still have a chance to create something good. I do not know what others here think about "Final Fantasy: The Spirits Between", but I liked it. It was not based in any game, and it does not try to resemble any game. Some fans expected the movie to do it, and hated it for having gone a different way.
But the movie followed its own story and conventions, while using concepts, themes and moods from the games (and doing it well, in my opinion). So we get a movie where the game's battles are not evident, but we get the heroin in a quest, that quest grows larger than she expected, opposition gets more powerful, and may not be entirely wrong in their beliefs or motivations, and by the end the quest reveals mysteries about the whole world and life in general.
So, I simply hope they do not try to make something that looks like the game and focus on a good sci-fi story about a material using as the building blocks of reality, or something like that.