I know Dan S. does a chat on Fangraphs sometimes. Feel free to take it up with him
I'd agree with you, I think Acuna should be just as good offensively as Soto, but I'm not the one to rate the players. You have a few options:
-Live with it
-Manually edit the ratings in commissioner mode
-Use the live updating function to pump Acuna up when he hits a HR every game over the opening weekend
And I do think he'll still perform with those ratings. He's average to above average in all the key ratings, and should be a plus defensive player. No, he won't have Trout-like seasons, but should still be a great player.