Needs are pointless, you can always trade from surplus for depth. If Davis is the BPA, you take him and trade him down the line if need be.
These guys are 2-4 years away from playing in the majors and a lot can happen in that window.
Also, the Tigers have been tied to Davis and have been said to really like him (they like Leiter too). So I wouldn’t rule them out drafting Davis just because they have a catcher in their system,