Not sure that I've ever had a package delivered by Amazon, but if I did there weren't any problems. That UPS incident is my only personal shipping issue in years.
Just like you mentioned, it was really bad at first. Packages would routinely arrive late, wrong address, etc. I live in a gated apartment complex and they would always leave the package with the leasing office instead of using the code I provided (UPS, FedEx, would always leave at my door).
Now it is indistinguishable from other carriers, in that all my packages arrive on time, at my door, without any problems.
The only thing I don't like is PrimeNow, which uses 'part time' carriers like Postmates, and they ALWAYS get confused by my apartment complex - so I stopped using it.
UberEats on the other hand can never find my house as their routing sends them down an alley that has no street numbers.
I wish I could say the same. I get calls from UPS delivery guys/gals about 30% of the time because I live in a duplex and my unit faces the alley. So they come in through the main street, can't find "Unit B" and end up calling me. I have to explain to them that they have to enter through the gate on the side.
This one time they left the package in front of the mailboxes, out in the open. When I got home, the entire box was soaking wet from the rain. Gross.
I've had Amazon Logistics carriers: Be unable to find my door (it's a non-gated, outward facing door in a row-style townhome with street access). Leave things at an _entirely different_ residential complex, whose address matched neither my street name nor number. They've done this twice, and not even at the same wrong complex (the hint is it said "left at reception", and we don't have a reception area). Try to pressure me into letting them just leave something on the sidewalk outside a gated apartment ("would that be safe?").
I'm a Prime addict and I feel like my dealer just started cutting the supply. At least let Prime members opt-out of Amazon Logistics (hell, I'd pay extra in my annual fee to do so).