The real point is that today the judge criminalised every single unauthorised absence.
Not exactly. It's been criminal since the Education Act of the 1940s, but prosecutions were rare. Then Labour introduced fines in 2003 and it's been simmering since, possibly because the new form of sanction made the issue more visible.
Heads still have discretion, and the removal of explicit mention of holidays and a 10 day limit was the only real change (lots of commentary about the difference between special and exceptional, but no difference in practice).
There has been very little from the unions on this - bodies who are usually highly vocal. That pupils should be in school in term time is perfectly reasonable to many.
As is school-level responsibility for when that can be varied.