Support ult lines

So I just saw a post about Symmetra’s ult voice line (which is going to be fixed, thanks for that devs!)
Here the post:

While reading it I was wondering why the ult voice lines for the supports work different when they use it themselves.
We know that DPS amd tanks hear the same voice line that the enemies hear when they use their ult.
But supports don’t. They hear what their allies hear.
Does anyone here know why? I mean it’s not a big deal and I am not complaining. I just wanted to know if there is a special thought behind this or anything.