Even during tough on immigrations administration the number of illegals were at around 10 million annually.
That is 100 million in a decade mind you. Not everyone stays obviously, but large chunk does.
Now there are states where latino are majority and even nationally are becoming a major voting block.
And now we literally have big faces of the democratic party like Sanders and AOC to call for halt in deportation, break up agencies responsible for guarding borders or even abolish ICE.
While not exactly coming out in to open and saying open border, there is no way that the illegal immigration numbers wont go up.