The absence of the wall charger reduces the phone’s overall packaging size which is supposed to help the environment. The A54 5G should have come with a USB charging cable, though.

Samsung Galaxy A54 5G | Unboxing

The absence of a charger in the box has been the trend over the last several years.  Started with the flagship phones and started making its way to midgrade phones like the A54 a year or two later.   In addition to environmental concerns, it also allows the cellphone makers to have a lower list price on the phone (or more profit margin depending on how popular they think the particular phone will be).