Unlike many other countries, Denmark tracked statistics based on immigration status and origin, and found non-Western immigrants to be economically a net-negative:
https://inquisitivebird.xyz/p/the-effects-of-immigration-in-... (includes link to official Danish govt. report)
An extreme instance of this is in slave societies. Slaves don't pay taxes and therefore are a net negative fiscally. Yet the taxes slave owners pay are largely drawn from slave labour and in fact the economy is essentially reliant on the slaves' work.
Likewise, it is possible that immigrants take on low-skilled, low-paid jobs, which are essential to the economy despite not directly contributing fiscally. This then could free the natives to perform more lucrative jobs and thereby contribute more than if immigrants were not there.
https://www.iwkoeln.de/fileadmin/user_upload/Studien/Kurzber...
> found non-Western immigrants to be economically a net-negative:
Not really. Some non-Western countries do have positive contributions.
"As of 2019, around 13.7 million people living in Germany, or about 17% of the population, are first-generation immigrants." - https://en.wikipedia.org/wiki/Immigration_to_Germany