I guess it depends on one's view of what "respect" means. I was always taught, and still believe, that respect has to be earned. You don't earn respect just by blessing the planet earth with your presence. If you screw up, your parents ought to respect you enough to say "you should've known better, and there will be punishment resulting." Whether that punishment does or doesn't involve spanking, I'm not sure I see a connection between that and "respect", because I don't know how the word is being defined.
I completely disagree.
Respect is something you should have from day one, for everything and anything that has as much right to live, breathe, eat, sleep and be protected as much as you deserve to be.
Whatever rights you believe you may have as a human being - to shelter, warmth, protection and nourishment, in whatever measure keeps you functioning - then other beings have that equal right.
And if you believe you have a right to be respected with regard to your opinions, politics, religion, gender and colour - then anyone else has that right too.
Regardless of age.
Respect for another being is a fundamental quality.
Now, that some people may either grow in your mind, and deserve a greater measure of respect, due to their words and actions, is one thing.
That some people may lose some of your respect, due to the things they say and do, is another.
But fundamentally, every human being has a right to Dignity and Respect.
And part of this respect means never laying a finger on them in violence or anger, and certainly never without their permission.