What Europe should do RIGHT NOW: Make it extremely easy for US scientists to get long-term visa, create as many additional research jobs in key areas as possible, create new, generous science and research funds. People are losing their jobs over there NOW. Let‘s welcome them.
Give me a visa and a job teaching computer science with income sufficient to live well and I'll be there tomorrow.
Please keep in mind that some of us with the experience and wisdom to be the good teachers you need are over 60 years old. Immigration policies often exclude us, but we know what we're doing.