So let's say we have a 'competitive' field of 40 cars. There will be cars that run up front, cars that run in the midfield, and cars that run at the back, regardless of how equally 'competitive' the field is. Therefore, those cars that run in the midfield and at the back will still be considered mid-pack and backmarker teams.
The point I'm trying to make is that no matter how 'equal' the field is, there will ALWAYS be cars and teams that are considered to be mid-pack and backmarkers regardless of how many 'competitive' cars the field has. Even if you get rid of current teams you consider to be backmarkers, all you would be doing is moving the competitive bracket up. But you CANNOT get rid of the idea of mid-pack and backmarker teams.