Its as if you arent reading the entire thread. You cant extrapolate information based on one data point.
The DHS has never seen 500k border apprehensions in a year. FY 2017 showed 300k.
https://www.dhs.gov/sites/default/files/publications/15-17-APR_0.pdf
And no one is arguing that more cant be done. Reasonable people, however, argue that a wall is the least effective, most costly way to do so. You even agreed to that.