Overall the OG dining experiences sound pretty bad. I must say that a few points seem to be very nitpicky.
I don't think it should matter if another waiter or dining staff filled up the glasses of water instead of your main waiter. I went to a very nice steakhouse last month and there was a gentleman whose only job, from what I saw, was to refill water glasses at all tables.
Is it a negative if the waiter does not ask if you are celebrating an occasion? The steakhouse waiter did ask if it was a special occasion, but the other casual dining locations I've been to recently have not. I think the waiter asked in a joking way since almost every table at the restaurant was celebrating the same special event. I see that a couple of people mentioned that here.
The waiter that was wearing soiled clothing, is it possible that someone spilled food on his uniform while he was on that shift? What is the solution for that?
Throwing mints on the table, not checking on you during your dining, them having a angry demeanor, yes those are negatives and legitimate claims for poor service.
I don't think customers are responsible for poor service. Different places say they can't hire or keep employees and sometimes they are taking any warm body to cover the need. It is awkward to have the waiter there when you are calculating the tip. I've been to the chain restaurants that have the payment kiosk on the table and the waiter wasn't there to see what I was going to leave them.