I think we all get what you said and are going through. USPS shortcomings have only been highlighted in the last 3 mos.Having worked for the USPS for 25 years I may be able to give some insight. Two things are to blame. Covid, and the current crop of people willing to fill out a job application.
Covid - If you show signs, get tested, you are required to quarantine. I was tested 3 times, all negative and my Dr quarantined me for 14 days, despite my attempts to get back to work. There are those who work the system. Take into account some offices that reach their breaking point and some routes are going undelivered and getting rotated based on available people to work. Management is carrying routes and people who've never carried mail in their life are being pulled from behind desks to keep the mail stream going. Sometimes its still not enough. No figure in Amazon, eBay, Kohls, et al, the holiday season and "overwhelmed" doesn't touch what is happening to many offices.
Work force - the simple fact is most young people simple don't want to work. Manual labor having to be out doors in foul weather? Blasphemy. Starting pay for my job was ~$16.25/hr about 6 months ago. Add in you can be required to have a vehicle that can be driven from the right hand side. Either a RHD Jeep or things like a Buick Le Sabre (split bench), find an old Taurus with a split bench. OR Pay to have pedals and a steering wheel mounted on the right side. Then you are required to maintain it (though the USPS pays you around .70/mile to do so). Now add in most young people don't know how to change their own oil and cost of professional maintenance can make this cost prohibitive VERY quickly). In my craft you can wait 10-12 years for a full time slot. I waited 10. City mail usually requires walking 10+ miles a day in all weather in any climate. Kids who grew up in front of a video screen scoff at such a thought. Factor in free money from the Gub'ment and extended unemployment benefits bringing home more than when you were working and the storm begins to brew.
Out of 10 applicants, maybe 6/7 will pass the entry test and get an interview. Of those half will actually show up for the interview. The other half are a no call/no show. Of those who show half will walk as soon as they are told it isn't a full time position and you are required to provide your own car or take extended walks in the rain and snow carrying a mail bag - despite the job application previously given this info when they applied online. Of those who stick with it and go through initial training, half of those will quit due to the nature of the job despite Post Masters bending over backwards giving extra training hours and residual help to get people over the hump. In the past 10 years, every female I've trained, or seen trained, ends up in the parking lot crying over the nature/stress/memorization requirements of the job. Not a slight at the female gender, its just a fact. So, out of 10 applicants, you are very lucky if you get one who is employed more than 3 months.
Go into the sorting plants and there are so many workers per supervisor, especially in large cities, its a known problem that people will come into the plant, clock in, and leave for the day, come back and clock back out. A lack of work ethic. The plants aren't empty, but it happens. I've personally had a few packages take 4 weeks to travel 50 miles and back track on itself. I know why, but suffice to say it got tossed into the wrong cart.
The vast majority of postal workers have a superb work ethic and go above and beyond. 99% of carriers really do like our job. Remember it is rarely your carriers fault you don't have your package yet. The USPS has fallen into the trap that a breathing body is better than no body so people can get hired based on the fact they are willing to show up. Though most of those get fired quickly, but it does happen.
Feel free to ask questions, I'll answer as best I can.
I can wait for almost anything I purchase, if not, I will settle for a local buy. I just want or need to know my 3500 Nightforce scope is moving along it's intended route, I am fine with a couple sleepovers. That keeps thoughts of it not making it past Davenport IA, and is now mounted backwards on some idiots AR 15 off my mind.