What about when they're temporary, and go back home with their money?

That's not an "immigrant", that's a seasonal migrant worker. Typically not legally capable of competing with legal citizens. They're picking fruit, not edging you out of a Target cashier job, much less anything else. If they're actual immigrants, and not seasonal workers, this is home.

What about when they come from a country so desperate and poor that they're terrified of being forced to go back, and so they'll do anything for work, even work half of minimum wage? You don't think that might drive down wages?

If they live here, they live here. If they're legally able to apply to jobs that pay above minimum wage, why would they be forced to go back? Are there any employment-dependent visas for minimum wage work? I'm certainly not aware of any.

What if they're so terrified that they won't form a union? Shouldn't the IWW care about that?

What?

What if this is all a trick by the capitalists themselves?

Immigration? I mean yeah, they're the driving force behind seasonal migrant workers. But actual immigrants?

And? I'm talking broadly about the economy, not one particular business.

Ya, that's the point - for a particular designation, the wage will have downward pressure, but for workers as whole the distribution of wages gets an upward pressure.

You can point out a couple of flawed studies against a mountain of contrary evidence.

https://www.congress.gov/118/meeting/house/116727/documents/HHRG-118-JU01-20240111-SD013.pdf

Intro

Today, the United States is home to the largest immigrant population in the world. Even though immigrants assimilate faster in the United States compared to developed European nations, immigration policy has become a highly contentious issue in America. While much of the debate centers on cultural issues, the economic effects of immigration are clear: Economic analysis finds little support for the view that inflows of foreign labor have reduced jobs or Americans’ wages. Economic theory predictions and the bulk of academic research confirms that wages are unaffected by immigration over the long-term and that the economic effects of immigration are mostly positive for natives and for the overall economy.

Key points

While some policymakers have blamed immigration for slowing U.S. wage growth since the 1970s, most academic research finds little long run effect on Americans’ wages.

The available evidence suggests that immigration leads to more innovation, a better educated workforce, greater occupational specialization, better matching of skills with jobs, and higher overall economic productivity.

Immigration also has a net positive effect on combined federal, state, and local budgets. But not all taxpayers benefit equally. In regions with large populations of less educated, low-income immigrants, native-born residents bear significant net costs due to immigrants’ use of public services, especially education.