I think you don't understand how bad some parents can be.
I do(know/knew friends with such parents, actually).
* Said parents are not going to agree to counseling or therapy, or if they are, will insist on choosing the therapist (which can result in some serious problems)
That possibility shouldn't make one feel like tossing the idea aside entirely, though, or be dissuaded from such.
Heck, if we all didn't do anything because bad things might happen nothing would get done and we'd all stand around in a state of mental paralysis.
* Said parents are at least a threat mentally. In some cases, it's bad enough that simply having the parents alive can cause mental stress; why should one cherish the lives of those who cause harm to them? (It is normal for said children to feel relief when the abusive parent dies, though be aware that said situation is complicated.)
Because they are only there because of them, and they are still family?
Also one can and sometimes should be able to be the "bigger person" and be able to love or even just tolerate those that have done somewhat bad things.
* The parents I am referring to are the sort who do not deserve respect, therefore their children should not be told to respect them.
No one is telling anyone to do anything here....and imo almost
everyone deserves respect in general to some degree for their good aspects or any good they have done.
Sometimes reconciliation is not possible.
Even so, I don't think people should assume such, give up to everything & and not even try.