The thing is, it's easy to say in a general way that people ought to be able to stand on their own two feet by such and such age, and that if they're not they're doomed - sink or swim etc. I imagine it's a lot harder if you're not talking about students as a whole but just one person, your child or family member, and you suspect they're sinking.
I would imagine that some of the types of phone calls where people are asking if their child is attending lectures or how they're doing could come from that sort of scenario. The hand being held out by the parent then might not be one that refuses to let go but one that's just offering to help and is struggling to find the right way.
I don't think any parent should be rushing in and doing things for their kids willy nilly, trying to lead the way in decisions, relieve them of all responsibility and so on. Helicopter parenting, I agree. On the other hand, just waving them off and disinterestedly observing three years later whether or not they've got a degree, with no interest taken in between, in the interests of 'letting them sink or swim' - that would be going too far to the opposite extreme. You can help without doing something for someone else. You can give someone guidance to get out of a mess and leave them with the skill to do it for themselves next time. Academic skills and life skills aren't exactly the same thing and some people can be further ahead with one compared to the other.
Not every student who fails is just lazy or disengaged and deserves to be left to sink unhelped. University pastoral care is an emergency safety net but no substitute for friends and family noticing and being interested in what's happening to a person, before things have gone so badly wrong that they can't be helped and end up dropping out. (Can you tell what nearly happened to me?)
I can see the problem with data protection etc. and that parents ringing up to get information just may not work, it might be the wrong way to go about it. But I think it's making a sweeping generalisation (and a bit callous) to imply that any parent interacting directly with a university must be a helicopter parent who is only motivated by a stupid desire not to let go, and that anyone who ever relies on the help of family ought instead to be somehow filtered out of the academic gene pool and just left to sink.