Netherlands is keen on receiving 'highly skilled migrants', aka tax paying citizens. There is a temporary tax discount for expats called the 30% ruling. But I think the discount is only fair because expats coming to Netherlands didn't receive benefits yet, and moving in general is also expensive.

It very much is, they skip the part of someone's life where they just cost (a lot of) money and get right to the part where they are making money of them.

Expats even get tax breaks to incentivize them to come here. Which is fair IMO. However it sucks big time for the countries they leave behind (brain drain, net negative financial impact).