the 10 year rule, how common is it and how is it enforced

"...I haven't worn a tie since I retired,..."
Me,too! In fact, I rarely wore one BEFORE I retired. Never could see the logic in tieing a noose around you neck and wearing it all day long.
I also quit shaving when I retired. Another barbaric custom, attacking you face with a sharp blade every morning. Disgusting habit!
I avoid places where either is required (including RV parks. Luckily, I have never found one that didn't allow a beard, or required a tie!)