I think a lot of folks here are describing Rafeala's weakness accurately, but in a manner that others might not understand by simply looking at his slash line.
Rafeala's biggest issue is his discipline. Which doesn't mean he doesn't walk or that he strikes out too often. Rather, it's that he attacks everything and whiffs frequently in the zone. He also makes a decent amount of bad contact (which masks the K numbers).
He needs to be more disciplined. but the impact of his aggression manifests itself differently than a guy who strikes out all the time.
Now if he's in the majors, where pitchers can beat you in the zone routinely, that k rate probably climbs.
How much weak contact does he make, really, though? His career BABIP is pretty normal, .307. Below average, actually, for the start of his career. In 2021 he posted a mark of .288; but since then, in about 800 PA, he's posted .409, .310, .351, 347. Am I wrong in thinking that's a long time for a guy to have a BABIP of .350 without him hitting the snot out of the ball every time he makes contact?
At the end of the day, his K rate is, yes, over 20%, but it's also not that far above 20%. His minor league numbers compare to Bichette's unfavorably, but not unfavorably enough for me to be in a panic. I think he, with any luck, puts up a wrc+ of around 90 or so while giving gold glove defense, which is really valuable. We're also underrating his pop, I think: 38 home runs over the last two years, with a couple of months to go, is nothing to sneeze at.
Larger point is well-taken, though. He will need to learn to lay off stuff out of the zone or he's going to quickly find himself carrying his weight as a glove-first guy who hits a clutch of home runs.