Cubs have eluded that Caissie and Alcantara aren't going to be on the bench, they want to give them full-time AB's in Iowa. Alcantara only has 35 career games in AAA. He'll be out of options after this season so I assume he'll be up at some point again if/when injuries happen, especially in the 2nd half. I also assume they want to give him as many Iowa PA's as possible while he's still able to play there this season.
There's plenty of time to change their launch angles once they come up. I'm not overly concerned, and they wouldn't count on them as middle-of-the-order mashers right away anyways. Would rather this path than the Ian Happ path of hitting development.
In his cup of coffee last Sept according to Bball Savant, Alcantara showed well-above average bat speed and 92nd percentile sprint speed. That would make him easily the 2nd fastest player on the team. And those metrics could go up with more data. The raw power is there.