I saw your video about this and was really interested, however already in the video i noticed some game design decisions that i feared would make this not a proper soft-body tetris as intended, and my fears were unfortunately correct. The blocks sticked way too fast once they hit something, making this more of a "glue-body Tetris", making the whole point of it being soft body pointless.(my suggestion, they should only start to stick once they stopped moving for 1-2 seconds, regardless of how much they may fall down) Plus it is too easy to make lines, i think the percentage should be higher.
The actual soft-bodies in the early version of the game looked amazing, exactly what i was hoping for when i found out someone made an actual soft-body tetris.
There was also some other minor issues, like the rotation speed not fast enough, or that you can't move a block anymore once they barely touch another block, or that the next block comes too fast down(there should be a rough 1 second waiting period) all decisions that could be changed(if desired) in a few seconds of coding.
And like you said in the video, once too many blocks are on screen it started to lag on my weak laptop, but that's expected considering the method you used to make the softbodies.
The actual execution is awesome! Plus the aesthetic designs are great as well. Just some gameplay decisions don't really fly with me ;)