i think the logic would be to incentive becoming a resident of the USA through legal means instead of just coming over illegally. if you increase the quota, you increase the speed of the bureaucracy and people who apply will feel more like waiting and doing it right will pay off. once those people are legal, they are less prone to labor exploitation, thereby reducing their impact on minimum wage as opposed to just not letting them in legally, and then having them come over illegal and ripe for exploitation.
and i agree, i think wages should be taken into account when evaluating immigration, but with a huge border that we cant lock down, it is all kinda just moot. the people will get in and take whatever job an unethical job creator will give them, their numbers will ebb and flow based on that, and not so much on what the government is doing.
at this point i see legalization as mitigating the illegal labor exploitation which can at least reduce the damage to wages. more pressure needs to be put on employers so they will be too afraid to hire illegal workers. in arizona we see on our local news every once in a while a local business owner getting locked up over identity theft because they allow workers to use stolen SSNs. those arrests, however, are too few and far in between at the moment. sherrif joe arpaio gets more glory chasing mexicans when the cameras show up, but not chasing these gringos in the offices hiring these people over americans or using them to undermine american workers.