If anything, these policies harm the citizens of the US in a myriad of ways. There's zero benefit to be had from any of this. Except for the joy tha tthe cruel feel in causing others misery, but that's not citizens, that's just a few sick people.
From the article:
"Updated guidance and training were being put in place to ensure that visa applicants don’t become a public charge under U.S. law or depend on government benefits intended for Americans in need, a spokesman for the department said Wednesday."
Whatever updated guidance and training is needed here is one of two things, 1) something that could be handled in a matter of days or weeks, or 2) "We have no idea how long this could take so we're suspending it indefinitely" (which is what they're doing), and the "updated guidance and training" is a smokescreen for Steven Miller's agenda of becoming a closed nation.
It's very clear what the motivations are, and just because they don't seem harmful in isolation doesn't mean it's going to have no consequences for everyone else.