Yes, I think middle schools should have reading specialists, or the equivalent. In my middle school we had "resource room" which provided support in all areas but was particularly strong in reading. The key in our school was the resource room teacher who had elementary teaching experience and was very familiar with techniques for teaching reading.
I'm certainly not a foe of formal reading instruction, but I'm convinced that students really develop their reading skills simply by reading and continuing to read. I can't count the number of high school students I've had who have told me the last time they had read a book "for fun" had been in elementary school. My students who read well were always those who had never stopped reading; as they grew older, their tastes changed and their reading books became more difficult as a natural transition.
I've also learned, though, that students who don't read well don't hate reading--they hate struggling and failing. It's no fun to go for a bike ride if you fall off the bike every 45 seconds. If I ruled the world, I would institute middle school and high school reading programs that put the right books, magazines, websites, and newspapers into kids' hands every day and give them time to read "for fun" until they eventually caught up. And by "right," I mean the materials that genuinely interest them and don't scare them away.
There are so many distractions these days--computer games, TV, texting, etc.--that most students refuse to make time to read for pleasure. Parents are partly to blame for not insisting that students read for pleasure for at least a short period each day. Many of my students absolutely refuse to read unless it is specifically assigned and do little other reading aside from their school work. As in so many other things, practice makes perfect; reading scores won't improve unless kids have a desire to read and are willing to take reading more seriously.
I agree with ask996 that the heavy emphasis on reading for information that starts in late middle elementary school contributes to the decline in reading proficiency scores for middle school students. I disagree, however, that the only answer is a reading specialist, although I believe that reading specialists are valuable.
Most middle school teachers are focused on content areas--they, like high school teachers, do not see themselves as teachers of reading. If content area teachers, beginning in grades 5-6, spent some time instructing students in HOW to read the textbook and other information in the content areas, I believe you'd see better reading scores across the board.
The reading specialist should be used primarily as a resource to help content teachers learn how to teach reading in their own content areas, NOT as a pullout resort for content teachers who are lazy and/or unwilling and/or untrained.
One of the reasons middle school students might be testing lower is because some of them stop reading and improving. Based upon the response of many of my unmotivated high school students, one reason for this is that school gets much harder. Where reading for pleasure was something they were encouraged to do in elementary school, they are hammered over the head with reading for information. When reading takes place in the literature classroom, quite frequently the material is squeezed so hard by the teacher, in order to get every last drop of learning out of it, that the reading of even what students would consider good loses any interest for many students.
I definitely feel that middle schools should have reading specialists or reading recovery teachers. In our district we provide reading support through second grade and students make progress and seem to do okay until late third grade or fourth grade. If we could find a way to provide continued support I think we would see improved reading scores at all levels.
It all depends on what you mean by standards and proficiency. Not all students are testing below state requirements or federal guidelines. With more and more distractions in the schools, everything from behavioral to social influences out of the class, most school systems have weakened their own positions.