"The Twins didn’t necessarily mis-evaluate Steer; they just chose to sell high when his value peaked."
Mahle had been injured, and the Twins knew it, as the whole league did. The FO just had a stiff desire to get him from the recent past. Mahle had just had a couple of starts off the IL, or was it the DL then...... and he quickly reinjured his arm, and then again the next season quickly.
The Twins did necessarily mis-evaluate Mahle; they chose to ingnore his injured status.
This was a dumb trade from the get go, to trade for an injured player, and they way over paid on top of it.