From the USA? Tbh, yes but only with a cut-off date. If they came before that date or have lived in the US for a certain amount of time they shouldn't tho
It's simply unreasonable from an economic standpoint to deport them all. Put tighter regulations on companies and schools in order to catch any illegal immigrants and allow them to pay for a visa and put them on a path to permanent residency or force them to leave.
So many people take the legal route, yes. BUT if they are going through the process to be legal (which can take a long time) then no. As long as they don't break the law during their application process, I don't see I an issue with it.