Supposedly are 2.5 in the morning and 3 at night. I.e. solid zone 2 workouts. Note they are using numbers from testing and their LT isn't at 4. It is right around 3. 2 and 4 are good starting points but you need to use your athletes actual values not those for populations.
But sure call them zone 1 workouts. You still aren't doing polarized training. Polarized training doesn't say do 80% of the work in zone 1. It says do 80% easy. Easy is down at ~70% hr and lactates closer to 1 than 2.
You would be better off arguing that they are really zone 3 workouts. But they really aren't. They are zone 2 workouts. The exact ones your supposed to be avoiding.
It is a classic pyramid program with a base of slow running, lots of quality threshold, and a bit of fast stuff (x days)...
I am sure if you asked Seiler would hand wave and count those threshold runs as quality. It is what he did for Seidel's program with all it's threshold work and MP work. His general point about threshold being bad was more about the stuff that was 30s too fast to be easy but 30s to slow to be quality work. Again not too many people would disagree with that.