Good grief, it's not a "downgrade." It's common journalistic practice for Presidents of both parties and perfectly acceptable.
The media refers to President Obama... Mr. Trump. What does that say to you?
It’s acceptable, today, you mean, which is no compliment necessarily.
In fact so much tradition, and respectful treatment of it, is lost. Ignorance and modernity is the preference and result.
I will say that given the moral low bar, or even the intellectual vacuum of recent presidents, because of that, Trump is bigger than the office he now holds.
Baloney! It is used to AVOID addressing the President with his legal title. Suppose you had called General Patton mister or president Kennedy, mister. What do you think the scale of the outrage would have been?