Your diatribe seems based on a projection.
The implication I glean of namdnay's point is that woes could be alleviated by immigration, and the responding user suggests that it's not a silver bullet. That's different than saying "everything is going to shit because of immigration".
Also, being critical of immigration policy is not tantamount to criticizing the immigrants themselves. That's another projection.
There are surely advantages to immigration, but I think it's disingenuous to suggest it has zero potential downsides especially with higher rates as other policies and structures don't necessarily shift in tandem to accommodate it.
For example, wage suppression - it's just simple supply and demand, which should be uncontroversial. But maybe one that might speak to some people more: everyone in the West has a higher carbon footprint, and no one moves here to consume less. The things we enjoy and take for granted are what make it a better life. So any conceit of potentially lowering waste/emissions qua consumer choice is wholly undermined by the fact that it is a matter of policy to increase consumption - with more bodies - to boost the GDP. Rates of global emissions are growing not just through growing economies like China (which is probably the largest factor of the last 20 years), but immigration.