Just a question, why aren't they using something like Zen2 at least or Zen3? Are these chips mostly for washing machines? /s

I can take a wild guess. This is embedded, so the cpu has to work in an environment 24/24. Desktop grade hardware is usually tested in a 8/24 cycle. I remember reading that a WD blue HDD was rated for 3 years warranty with usage of 8/24 while the nas version, though only 2 years, was 24/24. So, these should e a different revision compared to desktops were all hw bugs should e fixed and they should work reliably for many years, like 10+. Validation for such environment takes time, that is why car safety critical chips are build on 90/65, maybe 45nm process because it is true and tested and because they know all the manufacturing issues that can appear. Otherwise it is too risky.