Hard disagree on nested ternaries, or rather chained ternaries, which are just as easy to read and reason about as chained if else statements:

  if (isA) {
    return A;
  } else if (isB) {
    return B;
  } else if (isC) {
    return C;
  } else {
    return D;
  }

is equivalent to

  return isA ? A : isB ? B : isC ? C : D;