If the talk around Alaba is true these relatively low-cost options will help bolster the team. Let's take a few things that we know:
It seems unlikely to me that the club would go out and make a big purchase this summer unless one of Mbappe, Haaland, or Camavinga become available at a price that Madrid can afford (in both fee and wages). So low-cost options like Alaba and Ceballos help bolster the squad while providing rotational options. The problem with these is if they come demanding starter minutes as they are unlikely to achieve those. Well Alaba might actually contend with Mendy for a LB position.