Not everybody has a super chill communication style with their family, and that's okay! Some families express themselves by interrupting each other and yelling passionately. Other families might not frequently articulate their support, but they communicate their love in other ways, like being present and doing acts of service. Some families have a dry sense of humor and show their love by making fun of each other. None of these qualities on their own are the makings of a family with toxic communication habits.
On the other hand, there are so many damaging ways a parent can communicate with their kids. There's the classic "I guess I'm such a horrible mother" whenever facing any criticism, but that's elementary stuff. What's much worse is hurling insults, making threats, and overreacting to minor slights on the child's part. The way a parent interacts with their kid when nobody is listening tells us so much, and these insane parenting texts are textbook examples of this phenomenon.