Thats why I never mention the T word once on my variation https://ihopethisisfun.franzai.com/
They can go after you for anything. Whether or not that would hold in court is a separate question, but they count on the fact that you would be probably unwilling to test it.
Would they go after the shapes? Possibly. See "Tetris Holding, LLC v. Xio Interactive, Inc.".
TETR.IO and Jstris are insanely popular games that have been up for years with no action against them since they aren't hosted on another platform/marketplace.
This is also why Apotris got 2 DMCA takedowns on both Github and itch.io 3 months apart from each other, but after hosting the game on my own site, they haven't taken any further action in the past 2 years while it has continued to grow in popularity.