Do you think the combination of the Endless tag and the Puzzle genre isn’t enough to cover this case?
Viewing post in Tag merges and suggestions
You're right, I hadn't noticed the Endless tag. You can search puzzle + endless but looks like not all devs have tagged their games like that.
Although I still think a tag like "Match-3" or "Tile matching" or "Pattern matching" or something like that would be appropriate. It's hard to pin down Tetris / PuyoPuyo games as a genre, but over the years it's become a genre unto itself.