> $500-700k/yr here in total comp (a realistic proposition for senior engineers in hot fields)

Sure, but that level is paid to maybe 1-in-25 staff/principal/distinguished engineers at the top handful companies which make up maybe 1-in-25 of total jobs in the industry (order of magnitude)?

So for the 1-in-500 talents in the German coding industry, maybe it might be a worthwhile consideration to move halfway across the world with their families, but for the 499 even doubling their salary isn't all that enticing...