The point I was making is that the ES...the top-of-the-line in 2015...had become the base model in 2017. Mitsubishi didn't create a new base trim name in 2017, they reused the top trim name from 2015. Mitsubishi took what was formerly an upper trim name and moved it downmarket with a corresponding reduction in features, just like Chevy and Ford did.
In 2015, there was not a trim level higher than the ES. By 2017, EVERY trim level was higher than the ES.
In 1957, there was not a trim level higher than the Bel Air. By 1975, EVERY trim level was higher than the Bel Air.