I don’t think so.
The homeless are not illegal aliens.
Illegals are taking up HUD and other low income housing though. Ben Carson is evicting illegals out of HUD housing nationwide right now.
So there is an argument that illegals are living in low income housing that would be available for citizens.
I don’t think that’s the idea. The idea is that the illegal aliens are displacing citizens, who end up homeless. As a lifelong Californian, I can attest that this is 100% true. The bottom of the private rental market in California is very inaccessible to nearly everyone except Hispanics.