They'd probably take it because there's a huge difference between using a katana/wakizashi and something like a flamberge, tulwar, rapier, longsword or khopesh (to sample from a few larger blade categories). Stance, blows, balance, very large differences, and don't expect a master of one to be a master of all.
Mechanically, taking a Swords specialty is just fine. However, it doesn't make as much sense from a thematic perspective.