Easy: because next to 100% of EU government computers run Windows and MS Office.
We're lacking VC funding, not skilled tech workers. Increasing visas for tech workers without increasing the funding just lowers wages which are already low.
Plus, EU visas are basically just rubber stamps anyway compared to how hard getting an H1B is.
Actually here's another unused pressure point, the EU can retaliate by making it as difficult for Americans to work in the EU as it is for EU citizens to work in the US. Why isn't it already reciprocal?
One facet could be increasing investment, VC and otherwise
_How_ you do that? I'm not sure, but I also doubt it's a completely unsolvable problem