I see two ways to look at developmental math courses.
One way is to consider them a way to give a quick start to students who belong in college but don’t know the math. It either can be a review for students who have been away from math long enough to forget* or a restart for teaching students who somehow missed learning it in the first place.
A second way is that we are doing what was discussed in the previous paragraph but teaching students who would not have previously been considered college level. These students need more time and effort. Many of them can learn the material, but painfully slowly and with a great deal of work.