Canada

That's a really interesting question.

Many of the newcomers are students and they have to pay massive tuition. So they aren't contributing directly to taxes, but they are contributing a huge amount to Canada's post secondary institutions. Like 78% of total tuition in Ontario. The linked article has some pretty wild graphs. It's shitty because that money is being sucked out of newcomers' home countries to fund Canadian institutions.

Meanwhile, our GDP per capita has apparently been falling since 2017. I don't know how that relates to immigration versus our crappy productivity. Apparently our tax-to-GDP ratio has inched lower, so I assume our taxes per capita have also shrunk, despite the growing population.

Conversely, the spike in immigration has been in the last decade or so. A lot of the missing infrastructure takes longer to spin up: it's a decade+ to train medical staff. It's five+ years to train a teacher. Even planning and building transit can take a while. A sensible approach would be to plan for a growing population by getting more doctors/teachers/busses/houses ready before increasing the population, but it sounds like we didn't do that.