Look:
Aaron Civale is proof that the “sinker” is not dead.
The term, more and more, is used to describe all pitches that are neither four-seam nor cutter, but still of the fastball variety. A sinker is a pitch that is specifically designed to induce ground balls by dropping while near the hitter. A two-seamer is different, despite everyone recently deciding that both pitches are really the same thing.
While a two-seamer and sinker may be the “same pitch” when it comes to aggregating data across the game, it is clear that some pitcher favor horizontal movement and others seek to increase drop.