Trump apparently found room for both Busts.
As per the article, he has temporarily moved the older bust from the private residence, where Obama kept it after it was repaired, to the Oval Office. It does not seem he will have both busts in the office at once. Meanwhile, Trump's overall design seems to be refashioning the office to mimic its appearance under W Bush, with some degree of influence from the Farage connection.

So how is Trump less qualified than Obama?
That's rather glib. Of course if we stretch our parameters wide enough we might discover many tens of thousands more or less qualified to hold high office compared to past holders. Any number of politicians, corporate executives, professors or generals. Has there ever been an unqualified candidate, in fact?