Phillips didn't have a reliable partner last year, which is why he's better suited for the third pairing.
This 2nd or 3rd pairing stuff, is really a misnomer.
What it comes down to is how much time do you play at ES, and against what quality opposition. And then, whether you play on special teams.
Phillips is still good enough to play steady minutes at ES against tougher than average opposition, which is to say, perhaps not the shutdown pair, but also not protected either. On special teams, he can certainly be part of the four man PK group amongst our D.
Whether that is a 2nd pairing or 3rd pairing, is really a matter of perspective and context. Maclean has certainly never tried to protect him, like he has other members of our D at times.
He's still solid in his own end, even if he gets beat here and there. And he's smart and plays relatively physical (although not a punisher), so he will still eat up some solid minutes for us. Not sure what your deal is with him.