At this point it's beyond whether to attend briefings or the decorum at press conferences. As a matter of sound practice and professional ethics, it's not clear he should be interviewed at all. Of course journalists will continue to do it, but the why reasoning is breaking down.
For example, from a "first do no harm" POV, which is one ethical system, I don't believe you can justify an interview with the president any longer. I'm not saying that settles the matter, but it is true.
Or suppose you grounded your coverage of the Trump presidency in a simple, common-sense goal, one that should be easy to get consensus on. "Let's do everything we can to avoid misinforming people." Under that logic you would not interview him— because that would defeat your goal.
