My understanding, as well, is that as much as the tenure track situation in NA is on the disastrous side of bleak, the European and specifically UK tenure track

My understanding, as well, is that as much as the tenure track situation in NA is on the disastrous side of bleak, the European and specifically UK tenure track (or equivalent) situation is almost worse. I know you pointed out salaries, but the vast majority of junior academics are not interested in chasing higher salaries. They are there for their research and the opportunities to pursue that research.