Most of the time I initiate contact with Amazon customer service, I seem to get a custom response. When pushy, I have gotten excellent custom responses.
I expect Amazon does far more revenue/customer, though.
Not just more revenue per customer, but also the more issues they solve for you the more you'll be able to pay. If Spotify fixes your problem you won't go "now I'll use you more and pay 2x". For Amazon that's a real opportunity.
Your mileage may vary - I've got plenty of Amazon support staff blatantly telling me I've got no consumer rights (both national and EU) "because Amazon rules", no matter how high you try to escalate it.
My local Amazon website customer service was also pretty good every time I had a need for it. On the other hand, the English customer support of Amazon.jp is just straight up terrible. Wanted to send back a damaged product which I had bought as new and which wasn't damaged during transportation. Sent an e-mail, asking for specific information regarding that return. Got reply lacking such information, asked again, different person answering, still unsatisfying answer...rinse and repeat. In the end, I had sent seven e-mails and got a reply from a different customer service representative every single time whose answers contradicted each other too even. Went with the reply that made the most sense and seemed the most right in the end and eventually got it returned (despite some wrong information still) and my money back.
Another thing regarding wrong information on their product pages: Reporting wrong product names/descriptions and providing sources via the website was pointless and they never fixed it. After the whole ordeal with the return, I took the opportunity to tell them directly. Was told to provide a source (URL to some official website for instance) since they need it to confirm that there is something wrong there. Gave them all the URLs which included product titles, product pictures etc but they replied that they can't "use" (whatever that means) the URL (despite saying I should link it) and I'm supposed to screenshot it, upload it and then provide a link to the upload (or send it directly I guess). Of course, after everything above and now this, I was already beyond fed up and just stopped bothering since I'm certainly not gonna do their work for them. That, in addition to a website that is just getting worse and worse and worse stopped me from buying there. No point in having a bad buying experience and also knowing that, if you ever have an issue, support is gonna be an experience that will make you want to flip any tables you see for at least a few hours.
I expect Amazon does far more revenue/customer, though.