head to head
Tetris 99 asks more than Blur, and the gap is execution.

Execution · Pure Mechanics
Arcade racing with Mario Kart-style power-ups bolted onto licensed cars.

Execution · Pure Mechanics
Battle royale Tetris where raw stacking speed decides who outlasts 98 opponents.
Blur leans Execution (Pure Mechanics); Tetris 99 leans Execution (Pure Mechanics).
Tetris 99 leans clearly harder on execution.
Blur
Racing lines and dodging shots demand car control
Tetris 99
High-speed stacking and finesse define survival
Tetris 99 leans a little harder on reads, though the gap is small.
Blur
Human racers bait and time power-ups against you
Tetris 99
Targeting and badge timing against humans matter mid-match
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Blur
Power-up pickups and incoming attacks add chaos
Tetris 99
Incoming garbage timing and piece sequence add chaos
Tetris 99 leans a little harder on optimization, though the gap is small.
Blur
Track knowledge and pickup routes are learnable
Tetris 99
Stacking theory and downstack efficiency are studied skills
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.