Some of the Tatis numbers are probably fueled by his ridiculous 20.5% HR/FB percentage. Again, short season so that is all we really have.
When you hit the ball as hard as he does, the HR/FB % is not really ridiculous.
TangoTiger recently had a
Twitter thread discussing how looking at a batter's top 50% of hard-hit balls will best teach you about the batter. The bottom 50% tend to get similar results from batter to batter, but the hard-hitting batters separate in their upper 50%, which is even better than looking at a simple average exit velocity for all of their batted balls.
I looked at all of the exit velocities for each at bat by Tatis last year and his median exit velocity was 99.1 mph. When you take the half of his balls he hit above that velocity, the average is 105.6 mph. TangoTiger found that players whose top-half of batted balls were 104 mph had a ridiculous wOBA of .841 on those balls. (A player with a top-half batted ball average of 94 mph would have a wOBA of .413, by comparison.)
His fly balls are hit hard. I looked at all of his balls hit at a launch angle of 25-50 degrees last year and the average exit velocity on those balls was 97.9 mph. When you hit your fly balls over 95 mph consistently, you are going to miss outfielders and leave the park. (If you don't hit balls that hard, it's probably better to aim for the 11 to 17 degree launch angle.)