As I read this, I am feeling very lucky, although sad for a number of you having trouble.

I haven't noticed any change in my mail service - in a small town in suburban Columbus, OH. I know many of the local USPS people personally (a benefit of small town living) and they all try to do a really good job here.

But in general, almost any monopoly or almost-monopoly service usually manages to provide declining levels of service over time.