Why do cards use the "(ability) / Other creatures you control have (ability)" wording?
The current template is easier for players to understand
From the horse's mouth:


What the point of making creature with &quot;Trample. Other creatures you control have trample&quot; when you can just put it as &quot;Сreatures you control have trample&quot;?

The former has proven to be less confusing to a larger number of players. Remember, the number one goal of templating is comprehension, not brevity.