Why are so many Gen Z's disowning family members?

Recent studies show 1 in 2 Americans are estranged from at least 1 close family member.  The bulk of these numbers are among young people.  What it is about prioritizing emotional safety and protecting 'your truth' and brings someone to a place of disowning a parent, for example?  There's great irony at play here where the very parents that sheltered their children from pain, difficulty, challenges and disappointment are now not being accepted in the lives of their children because it's too complicated or difficult.  To be clear, I am not speaking of anyone who has been abused by a family member, to be clear.  Boundaries in a situation of cruelty and abuse are very necessary.