Governments with heavy social programs can't risk losing anymore taxpayers at a time where their systems are already strained by a lack of workers/population decline. This seems like a preemptive measure to prevent that more than a result of privacy concerns.

Presuming these ulterior motives gets so tiresome. These bans are instated by data protection authorities, which largely operate independently. E.g., the Dutch data protection authority regularly fines the government. Pretty sure that is the case for other EU countries too.

You're welcome to disagree with my presumption but you don't appear to be stating anything definitive about this matter either.

All these governments have a duty to their aging population, which also tends to make up the majority of the active voter base. Every action they take tends to be multipronged but at the end of the day it's meant to protect those social programs. Consider mass migration to increase labor force and birth rates. Sure they can claim it was purely out of good will, but you'd have to be pretty myopic not to see the reality there.

You keep on conflating data protection agencies with governments. They aren't the same thing - the Garante per la Protezione dei Dati Personali is an independent administrative authority - and even the GP pointed that out.

I assure you, unless it's about multi-billion euro companies, the German state does not care at all whether they'll lose a tax payer or ten or ten thousands (source: me, a tax payer that gets fucked by the bureaucracy at every opportunity). Data Protection is taken extremely seriously and everything that is associated with "big data" is extra suspicious. Throw in "think of the children" for extra spice.

I doubt tax income on copyright dividends even registers.