That's pretty sweet, didn't know anybody'd broken 20s with keyblox (keytris in this case I guess)
To answer your question, it is generally understood that players are competing for the fastest time on the same basic game. Since keytris as demonstrated is not directly comparable, it's hard to say that a keytris record "counts" as the "world record sprint time." When we're talking world records, we generally allow for minimum delays and instant das, sonic drop, etc., but the basic game is the same: SRS rotation system, left/right rotate left/rotate right, soft/firm/hard drop, hold for inputs. This is the baseline by which speed records are comparable.
Having a more restrictive setup counts, but having a more lenient setup doesn't. For example, Hangame has some weird settings but they don't offer an advantage over our "ideal tetris", so they are applicable for the title "world record".
Records will often be qualified by the game/engine they were made on, but when not specified it is generally considered to be within certain boundaries.