
Taxes and housing
Such proposals often seem like suggestions to spend more taxpayer's money by the EU central government. But bureaucratic solutions are not the way to go.
Most Californian companies employ a lot of foreigners, including Europeans. So why do they move to California?
Solutions: stop taxing work; tax high risk investments less; and most importantly - kill housing/mortgage "business" once and forever, so that workforce can easily find a place to live near business centers.
The housing issue has plagued USA, Europe and recently China. It is this banking profiteering/pyramid that has caused recent enormous debt, money printing, and finally inflation. Housing must be regulated similar to energy supply monopolies, so that possible gains should never be spectacular, just reasonably sustainable and reasonably investable - like bonds. Don't allow banks easily create mortgage debt, so they are forced to reallocate their energy to financing entrepreneurship instead.
EU could also issue "green cards" to foreigners having high tech qualifications. Especially young. Multiple European languages are a substantial barrier by itself - so let's remove one.